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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Photothermal Response in Dual-Gated Bilayer Graphene M.-H. Kim,1  

E-Print Network [OSTI]

Photothermal Response in Dual-Gated Bilayer Graphene M.-H. Kim,1 J. Yan,1,2 R. J. Suess,3 T. E photoresponse in gapped bilayer graphene was investigated by optical and transport measurements. A pulse There is growing recognition that graphene has excep- tional potential as a new optoelectronic material, which has

Murphy, Thomas E.

2

Bilayer Graphene Gets a Bandgap  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bilayer Graphene Gets a Bandgap Bilayer Graphene Gets a Bandgap Bilayer Graphene Gets a Bandgap Print Wednesday, 26 August 2009 00:00 Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

3

Bilayer Graphene Gets a Bandgap  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bilayer Graphene Gets a Bandgap Bilayer Graphene Gets a Bandgap Bilayer Graphene Gets a Bandgap Print Wednesday, 26 August 2009 00:00 Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

4

Bilayer Graphene Gets a Bandgap  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bilayer Graphene Gets a Bandgap Print Bilayer Graphene Gets a Bandgap Print Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

5

Bilayer Graphene Gets a Bandgap  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bilayer Graphene Gets a Bandgap Print Bilayer Graphene Gets a Bandgap Print Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

6

Bilayer Graphene Gets a Bandgap  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bilayer Graphene Gets a Bandgap Print Bilayer Graphene Gets a Bandgap Print Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

7

Bilayer Graphene Gets a Bandgap  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bilayer Graphene Gets a Bandgap Print Bilayer Graphene Gets a Bandgap Print Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

8

Bilayers in nanoparticle-doped polar mesogens  

Science Journals Connector (OSTI)

Structures of the mesophases of five members of the 4-n-alkyl-4?-cyanobiphenyl homologous series (4-n-butyl-4?-cyanobiphenyl to 4-n-octyl-4?-cyanobiphenyl) doped with milled BaTiO3 nanoparticles were investigated by x-ray scattering. Clear solutions of each of the 4-n-alkyl-4?-cyanobiphenyls were first prepared in n-heptane and then doped with an n-heptane/nanoparticle dispersion, which led to gelation. The nanogels were found to be one-dimensional, multilayered, smectic nanostructures in each case. Surprisingly, a characteristic layer spacing of 4.5 nm was observed in all five homologues. Synchrotron x-ray scattering study of the multilayer structures of doped 4-n-pentyl-4?-cyanobiphenyl and 4-n-octyl-4?-cyanobiphenyl revealed nine orders of the primary Bragg reflection which were used to calculate the electron density profiles of the multilayers by Fourier analysis. The multilayers were found to consist of molecular bilayers wherein the mesogens were arranged in a head-to-head assembly of the polar head groups. The alkyl tails of the mesogenic molecules were freely movable and the tail-to-tail assembly was stabilized by heptane. The dissolved nanoparticles clearly induced a new self-assembled nanostructure in which the rigid aromatic part, and not the overall length, of the molecules defined the layer spacing.

Alexander Lorenz; Deña M. Agra-Kooijman; Natalie Zimmermann; Heinz-S. Kitzerow; Dean R. Evans; Satyendra Kumar

2013-12-10T23:59:59.000Z

9

Proximity-induced superconductivity in single-layer and bilayer graphene.  

E-Print Network [OSTI]

??In this work, the properties of proximity-induced superconductivity in graphene and bilayer graphene are investigated. We report the realisation and study of a dual-gated bilayer… (more)

Bordaz, Julien

2014-01-01T23:59:59.000Z

10

Doping efficiency of single and randomly stacked bilayer graphene by iodine adsorption  

SciTech Connect (OSTI)

We report on the efficiency and thermal stability of p-doping by iodine on single and randomly stacked, weakly coupled bilayer polycrystalline graphene, as directly measured by photoelectron emission microscopy. The doping results in work function value increase of 0.4–0.5?eV, with a higher degree of iodine uptake by the bilayer (2%) as compared to the single layer (1%) suggesting iodine intercalation in the bilayer. The chemistry of iodine is identified accordingly as I{sub 3}{sup ?} and I{sub 5}{sup ?} poly iodide anionic complexes with slightly higher concentration of I{sub 5}{sup ?} in bilayer than monolayer graphene, likely attributed to differences in doping mechanisms. Temperature dependent in-situ annealing of the doped films demonstrated that the doping remains efficient up to 200?°C.

Kim, HoKwon; Renault, Olivier; Rouchon, Denis; Mariolle, Denis; Chevalier, Nicolas [Univ. Grenoble Alpes, F-38000 Grenoble, France and CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Tyurnina, Anastasia; Simonato, Jean-Pierre; Dijon, Jean [Univ. Grenoble Alpes, F-38000 Grenoble, France and CEA, LITEN, Minatec Campus, F-38054 Grenoble (France)

2014-07-07T23:59:59.000Z

11

High-Performance Integrated Dual-Gate AlGaN/GaN Enhancement-Mode Transistor  

E-Print Network [OSTI]

In this letter, we present a new AlGaN/GaN enhancement-mode (E-mode) transistor based on a dual-gate structure. The dual gate allows the transistor to combine an E-mode behavior with low on-resistance and very high breakdown ...

Lu, Bin

12

Commensurate-incommensurate magnetic phase transition in the Fe-doped bilayer ruthenate Ca3Ru2O7  

Science Journals Connector (OSTI)

Neutron diffraction studies have revealed an uncommon commensurate-incommensurate magnetic phase transition with decreasing temperature in the (?5%) Fe-doped bilayer ruthenate Ca3(Ru,Fe)2O7. An incommensurate phase formed of a cycloidal spiral spin structure coexists with a commensurate one below the phase transition at 42 K and persists down to the lowest temperature, accompanied by higher-order magnetic satellite peaks which indicate the formation of a magnetic soliton lattice. We ascribe these findings to the competing magnetic interactions in this system. This study demonstrates an effective approach to tune novel magnetic and electronic properties of ruthenates via 3d magnetic transition-metal substitution.

X. Ke; J. Peng; W. Tian; Tao Hong; M. Zhu; Z. Q. Mao

2014-06-23T23:59:59.000Z

13

Bilayer Graphene Photon Detector J. Y. Yan, M.-H. Kim, J. A. Elle, A. B. Sushkov, G. S. Jenkins, H. M. Milchberg  

E-Print Network [OSTI]

Bilayer Graphene Photon Detector J. Y. Yan, M.-H. Kim, J. A. Elle, A. B. Sushkov, G. S. Jenkins, H in graphene suggests that "hot electrons" created by incident light can provide the basis for a fast graphene in a "dual-gated" structure. This new "bolometer" has ultralow noise, besting existing detectors

Shapiro, Benjamin

14

Bulk Heterojunction versus Diffused Bilayer: The Role of Device Geometry in Solution p-Doped Polymer-Based Solar Cells  

Science Journals Connector (OSTI)

KPFM images were acquired with a commercial AFM system (Bruker-AXS) MultiMode AFM with a Nanoscope V controller operating in lift mode (typical lift height 20 nm) by using silicon tips with PtIr coating (SCM-PIT) with k ? 3?N?m–1, tip radius ? 20 nm, and resonant frequency ? 80 Khz. ... Lee, K. H.; Schwenn, P. E.; Smith, A. R. G.; Cavaye, H.; Shaw, P. E.; James, M.; Krueger, K. B.; Gentle, I. R.; Meredith, P.; Burn, P. L.Morphology of All-Solution-Processed “Bilayer” Organic Solar Cells Adv. ...

Anna Loiudice; Aurora Rizzo; Mariano Biasiucci; Giuseppe Gigli

2012-07-09T23:59:59.000Z

15

Dynamical screening in bilayer graphene  

Science Journals Connector (OSTI)

We calculate one-loop polarization in bilayer graphene in the four-band approximation for arbitrary values of frequency, momentum, and doping. At low and high energy our results reduce to the polarization functions calculated in the two-band approximation and in the case of single-layer graphene, respectively. The special cases of static screening and plasmon modes are analyzed.

O. V. Gamayun

2011-08-22T23:59:59.000Z

16

Screening in gated bilayer graphene  

Science Journals Connector (OSTI)

The tight-binding model of a graphene bilayer is used to find the gap between the conduction and valence bands, as a function of both the gate voltage and as the doping by donors or acceptors. The total Hartree energy is minimized and the equation for the gap is obtained. This equation for the ratio of the gap to the chemical potential is determined only by the screening constant. Thus the gap is strictly proportional to the gate voltage or the carrier concentration in the absence of donors or acceptors. In the opposite case, where the donors or acceptors are present, the gap demonstrates the asymmetrical behavior on the electron and hole sides of the gate bias.

L. A. Falkovsky

2009-09-30T23:59:59.000Z

17

Bilayer Graphene Gets a Bandgap  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bilayer Graphene Gets a Bandgap Bilayer Graphene Gets a Bandgap Print Wednesday, 26 August 2009 00:00 Graphene is the two-dimensional crystalline form of carbon whose extraordinary...

18

Twist Solves Bilayer Graphene Mystery  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Twist Solves Bilayer Graphene Mystery Twist Solves Bilayer Graphene Mystery Print Wednesday, 26 March 2014 00:00 Researchers have discovered a unique new twist to the story of...

19

Bilayer Graphene Gets a Bandgap  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bilayer Graphene Gets a Bandgap Print Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise...

20

Cyclotron Resonance in Bilayer Graphene  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Resonance in Bilayer Graphene PI: Horst Stormer, Department of Physics, Columbia University Supported by NSF (DMR-03-52738 and CHE-0117752), ONR (N000150610138) DOE...

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Lipid bilayers on nano-templates  

DOE Patents [OSTI]

A lipid bilayer on a nano-template comprising a nanotube or nanowire and a lipid bilayer around the nanotube or nanowire. One embodiment provides a method of fabricating a lipid bilayer on a nano-template comprising the steps of providing a nanotube or nanowire and forming a lipid bilayer around the polymer cushion. One embodiment provides a protein pore in the lipid bilayer. In one embodiment the protein pore is sensitive to specific agents

Noy, Aleksandr (Belmont, CA); Artyukhin, Alexander B. (Menlo Park, CA); Bakajin, Olgica (San Leandro, CA); Stoeve, Pieter (Davis, CA)

2009-08-04T23:59:59.000Z

22

Optical Determination of Gate--Tunable Bandgap in Bilayer Graphene  

E-Print Network [OSTI]

Tunable Bandgap in Bilayer Graphene Yuanbo Zhang* 1 , Tsung-gate-tunable bandgap in graphene bilayers with magnitude asbands. In two- dimensional graphene bilayers this bandgap

Zhang, Yuanbo

2010-01-01T23:59:59.000Z

23

Twist Solves Bilayer Graphene Mystery  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Twist Solves Bilayer Graphene Mystery Print Researchers have discovered a unique new twist to the story of graphene and, in the process, appear to have solved a mystery that has...

24

Transverse electric plasmons in bilayer graphene  

E-Print Network [OSTI]

We predict the existence of transverse electric (TE) plasmons in bilayer graphene. We find that their plasmonic properties are much more pronounced in bilayer than in monolayer graphene, in a sense that they can get more ...

Jablan, Marinko

25

Phonons in twisted bilayer graphene  

Science Journals Connector (OSTI)

We theoretically investigate phonon dispersion in AA-stacked, AB-stacked, and twisted bilayer graphene with various rotation angles. The calculations are performed using the Born–von Karman model for the intralayer atomic interactions and the Lennard-Jones potential for the interlayer interactions. It is found that the stacking order affects the out-of-plane acoustic phonon modes the most. The difference in the phonon densities of states in the twisted bilayer graphene and in AA- or AB-stacked bilayer graphene appears in the phonon frequency range 90–110 cm?1. Twisting bilayer graphene leads to the emergence of different phonon branches—termed hybrid folded phonons—which originate from the mixing of phonon modes from different high-symmetry directions in the Brillouin zone. The frequencies of the hybrid folded phonons depend strongly on the rotation angle and can be used for noncontact identification of the twist angles in graphene samples. The obtained results and the tabulated frequencies of phonons in twisted bilayer graphene are important for the interpretation of experimental Raman data and in determining the thermal conductivity of these material systems.

Alexandr I. Cocemasov; Denis L. Nika; Alexander A. Balandin

2013-07-15T23:59:59.000Z

26

Cyclotron Resonance in Bilayer Graphene  

Science Journals Connector (OSTI)

We present the first measurements of cyclotron resonance of electrons and holes in bilayer graphene. In magnetic fields up to B=18??T, we observe four distinct intraband transitions in both the conduction and valence bands. The transition energies are roughly linear in B between the lowest Landau levels, whereas they follow B for the higher transitions. This highly unusual behavior represents a change from a parabolic to a linear energy dispersion. The density of states derived from our data generally agrees with the existing lowest order tight binding calculation for bilayer graphene. However, in comparing data to theory, a single set of fitting parameters fails to describe the experimental results.

E. A. Henriksen; Z. Jiang; L.-C. Tung; M. E. Schwartz; M. Takita; Y.-J. Wang; P. Kim; H. L. Stormer

2008-02-27T23:59:59.000Z

27

Deconfined criticality in bilayer graphene  

Science Journals Connector (OSTI)

We propose that bilayer graphene can provide an experimental realization of deconfined criticality. Current experiments indicate the presence of Néel order in the presence of a moderate magnetic field. The Néel order can be destabilized by application of a transverse electric field. The resulting electric field induced state is likely to have valence bond solid order, and the transition can acquire the emergent fractionalized and gauge excitations of deconfined criticality.

Junhyun Lee and Subir Sachdev

2014-11-19T23:59:59.000Z

28

Andreev reflection in bilayer graphene  

Science Journals Connector (OSTI)

We consider the differential conductance of a normal-superconductor junction in clean bilayer graphene in the framework of the Dirac–Bogoliubov–de Gennes equation. A remarkable suppression of the differential conductance at voltages just below the superconducting gap is found. This can be understood in terms of the spinor structures of the electron and hole excitations, in particular, the reflected valence-band hole being orthogonal to the incoming electron at normal incidence.

T. Ludwig

2007-05-18T23:59:59.000Z

29

Optical Transitions in Monolayer and Bilayer Graphene  

Science Journals Connector (OSTI)

Optical transitions in grapheme are studied by infrared spectroscopy. The interband transitions in graphene monolayers show a relatively flat spectrum, while those in bilayers are...

Wang, Feng; Zhang, Yuanbo; Tian, Chuanshan; Girit, Caglar; Zettl, Alex; Shen, Y Ron

30

STABLE HIGH CONDUCTIVITY BILAYERED ELECTROLYTES FOR LOW TEMPERATURE SOLID OXIDE FUEL CELLS  

SciTech Connect (OSTI)

A bilayer electrolyte consisting of acceptor-doped ceria (on the fuel/reducing side) and cubic-stabilized bismuth oxide (on the oxidizing side) was developed. The bilayer electrolyte that was developed showed significant improvement in open-circuit potential versus a typical ceria based SOFC. Moreover, the OCP of the bilayer cells increased as the thickness of the bismuth oxide layer increased relative to the ceria layer. Thereby, verifying the bilayer concept. Although, because of the absence of a suitable cathode (a problem we are still working assiduously to solve), we were unable to obtain power density curves, our modeling work predicts a reduction in electrolyte area specific resistance of two orders of magnitude over cubic-stabilized zirconia and projects a maximum power density of 9 W/m{sup 2} at 800 C and 0.09 W/m{sup 2} at 500 C. Towards the development of the bilayer electrolyte other significant strides were made. Among these were, first, the development of a, bismuth oxide based, oxide ion conductor with the highest conductivity (0.56 S/cm at 800 C and 0.043 S/cm at 500 C) known to date. Second, a physical model of the defect transport mechanisms and the driving forces for the ordering phenomena in bismuth oxide and other fluorite systems was developed. Third, a model for point defect transport in oxide mixed ionic-electronic conductors was developed, without the typical assumption of a uniform distribution of ions and including the effect of variable loads on the transport properties of an SOFC (with either a single or bilayer electrolyte).

Eric D. Wachsman; Keith L. Duncan

2002-09-30T23:59:59.000Z

31

10 - Electronic transport in bilayer graphene  

Science Journals Connector (OSTI)

Abstract: Electronic transport in bilayer graphene is studied in this chapter and the fundamental physics and conceptual issues are described. A model Hamiltonian system is described and the method for inducing an energy band gap in the system. The transport properties investigated include conductance in a p–n junction, the self-consistent Born approximation and RKKY (Ruderman–Kittel–Kasuya–Yosida) interactions in biased bilayer graphene. Studies on suspended bilayer graphene and on new-generation bilayer graphene samples on SiC are described and the role of many-body effects in these systems is explored. The collective modes in the symmetry and asymmetry charge density channels are discussed and use of the effective mass as an essential quantity in quasiparticle theories is examined. The charge compressibility in bilayer graphene is studied in depth.

R. Asgari

2014-01-01T23:59:59.000Z

32

Weak Localization in Bilayer Graphene  

Science Journals Connector (OSTI)

We have performed the first experimental investigation of quantum interference corrections to the conductivity of a bilayer graphene structure. A negative magnetoresistance—a signature of weak localization—is observed at different carrier densities, including the electroneutrality region. It is very different, however, from the weak localization in conventional two-dimensional systems. We show that it is controlled not only by the dephasing time, but also by different elastic processes that break the effective time-reversal symmetry and provide intervalley scattering.

R. V. Gorbachev; F. V. Tikhonenko; A. S. Mayorov; D. W. Horsell; A. K. Savchenko

2007-04-26T23:59:59.000Z

33

Antiferromagnetic state in bilayer graphene  

Science Journals Connector (OSTI)

Motivated by the recent experiment of Velasco Jr. et al. [J. Velasco Jr. et al., Nat. Nanotechnology 7, 156 (2012)], we develop a mean-field theory of the interaction-induced antiferromagnetic (AF) state in bilayer graphene at charge neutrality point at arbitrary perpendicular magnetic field B. We demonstrate that the AF state can persist at all B. At higher B, the state continuously crosses over to the AF phase of the ?=0 quantum Hall ferromagnet, recently argued to be realized in the insulating ?=0 state. The mean-field quasiparticle gap is finite at B=0 and grows with increasing B, becoming quasilinear in the quantum Hall regime, in accord with the reported behavior of the transport gap. By adjusting the two free parameters of the model, we obtain a simultaneous quantitative agreement between the experimental and theoretical values of the key parameters of the gap dependence—its zero-field value and slope at higher fields. Our findings suggest that the insulating state observed in bilayer graphene in Ref. 1 is antiferromagnetic (canted, once the Zeeman effect is taken into account) at all magnetic fields.

Maxim Kharitonov

2012-11-30T23:59:59.000Z

34

"Nanocrystal bilayer for tandem catalysis"  

SciTech Connect (OSTI)

Supported catalysts are widely used in industry and can be optimized by tuning the composition and interface of the metal nanoparticles and oxide supports. Rational design of metal-metal oxide interfaces in nanostructured catalysts is critical to achieve better reaction activities and selectivities. We introduce here a new class of nanocrystal tandem catalysts that have multiple metal-metal oxide interfaces for the catalysis of sequential reactions. We utilized a nanocrystal bilayer structure formed by assembling platinum and cerium oxide nanocube monolayers of less than 10 nm on a silica substrate. The two distinct metal-metal oxide interfaces, CeO2-Pt and Pt-SiO2, can be used to catalyse two distinct sequential reactions. The CeO2-Pt interface catalysed methanol decomposition to produce CO and H2, which were subsequently used for ethylene hydroformylation catalysed by the nearby Pt-SiO2 interface. Consequently, propanal was produced selectively from methanol and ethylene on the nanocrystal bilayer tandem catalyst. This new concept of nanocrystal tandem catalysis represents a powerful approach towards designing high-performance, multifunctional nanostructured catalysts

Yamada, Yusuke; Tsung, Chia Kuang; Huang, Wenyu; Huo, Ziyang; E.Habas, Susan E; Soejima, Tetsuro; Aliaga, Cesar E; Samorjai, Gabor A; Yang, Peidong

2011-01-24T23:59:59.000Z

35

Surface tension and electroporation of lipid bilayers  

E-Print Network [OSTI]

Electroporation of lipid bilayers is widely used in DNA transfection, gene therapy, and targeted drug delivery and has potential applications in water desalination and filtration. A better, more thorough molecular understanding ...

Cho, Han-Jae Jeremy

2011-01-01T23:59:59.000Z

36

Echoes of relativistic Landau levels in graphene and bilayer graphene  

Science Journals Connector (OSTI)

The problem of echo effects that can originate in graphene and bilayer graphene upon the generation of relativistic Landau levels in a quantizing magnetic field is considered. Graphene (bilayer graphene) is consi...

M. B. Belonenko; N. G. Lebedev; A. V. Zhukov

2012-03-01T23:59:59.000Z

37

Rate dependent rupture of solid-supported phospholipid bilayers.  

E-Print Network [OSTI]

An experimental study on solid-supported phospholipid bilayers was performed in order to investigate rate-dependent behavior of force and probability of bilayer rupture. 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine ...

Ng, Sarah S

2006-01-01T23:59:59.000Z

38

Dynamical Screening and Excitonic Instability in Bilayer Graphene  

E-Print Network [OSTI]

Electron interactions in undoped bilayer graphene lead to an instability of the gapless state, “which-layer” symmetry breaking, and energy gap opening at the Dirac point. In contrast with single-layer graphene, the bilayer ...

Levitov, Leonid

39

Possible mechanism of adhesion in a mica supported phospholipid bilayer  

SciTech Connect (OSTI)

Phospholipid bilayers supported on hydrophilic solids like silica and mica play a substantial role in fundamental studies and technological applications of phospholipid membranes. In both cases the molecular mechanism of adhesion between the bilayer and the support is of primary interest. Since the possibilities of experimental methods in this specific area are rather limited, the methods of computer simulation acquire great importance. In this paper we use the grand canonical Monte Carlo technique and an atomistic force field to simulate the behavior of a mica supported phospholipid bilayer in pure water as a function of the distance between the bilayer and the support. The simulation reveals a possible adhesion mechanism, where the adhesion is due to individual lipid molecules that protrude from the bilayer and form widely spaced links with the support. Simultaneously, the bilayer remains separated from the bilayer by a thin water interlayer which maintains the bilayer fluidity.

Pertsin, Alexander, E-mail: ig3@ix.urz.uni-heidelberg.de [Angewandte Physikalische Chemie, Universität Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg (Germany) [Angewandte Physikalische Chemie, Universität Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg (Germany); Institute of Organo-Element Compounds, Russian Academy of Sciences, Vavilov Str. 28, 117991 Moscow (Russian Federation); Grunze, Michael [Angewandte Physikalische Chemie, Universität Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg (Germany) [Angewandte Physikalische Chemie, Universität Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg (Germany); Institute for Functional Interfaces, Karlsruhe Institute of Technology, Hermann-von- Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

2014-05-14T23:59:59.000Z

40

Adsorption on tunable bilayer graphene: A model approach  

SciTech Connect (OSTI)

The problem of the adsorption of atoms on the surface of tunable bilayer graphene is considered within the context of Anderson's model. Analytical expressions for the densities of states of bilayer graphene and an adatom are derived, and the charge exchange between adatoms and bilayer graphene is studied. The charge of adatoms of some elements is estimated. The change induced in the density of states of tunable bilayer graphene by the adsorption of atoms is explored.

Alisultanov, Z. Z., E-mail: zaur0102@gmail.com [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)

2013-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Structure of the solid D2 bilayer on graphite  

Science Journals Connector (OSTI)

Low-energy electron-diffraction (LEED) measurements for a solid D2 bilayer physisorbed on graphite are used to investigate the bilayer structure and its azimuthal orientation relative to the substrate. The LEED spot positions are consistent with the mutually commensurate oblique unit cell inferred from neutron-diffraction measurement. Given the azimuthal orientation of the bilayer LEED spots, the possibility of a bilayer composed of two incommensurate layers with mutually modulated triangular lattices is ruled out.

Wei Liu and S. C. Fain; Jr.

1993-06-15T23:59:59.000Z

42

hal00276997, Raman spectra of misoriented bilayer graphene  

E-Print Network [OSTI]

hal­00276997, version 1 ­ 5 May 2008 Raman spectra of misoriented bilayer graphene P. Poncharal 1 spectra from single layer graphene with a bilayer in which the two layers are arbitrarily misoriented to the similarity of the electronic structures of single layer graphene and misoriented bilayer graphene. Another

Paris-Sud XI, Université de

43

Fabrication of Li-intercalated bilayer graphene  

Science Journals Connector (OSTI)

We have succeeded in fabricating Li-intercalated bilayer graphene on silicon carbide. The low-energy electron diffraction from Li-deposited bilayer graphene shows a sharp 3 × 3 R 30° pattern in contrast to Li-deposited monolayer graphene. This indicates that Li atoms are intercalated between two adjacent graphene layers and take the same well-ordered superstructure as in bulk C6Li. The angle-resolved photoemission spectroscopy has revealed that Li atoms are fully ionized and the ? bands of graphene are systematically folded by the superstructure of intercalated Li atoms producing a snowflake-like Fermi surface centered at the ? point. The present result suggests a high potential of Li-intercalated bilayer graphene for application to a nano-scale Li-ion battery.

K. Sugawara; K. Kanetani; T. Sato; T. Takahashi

2011-01-01T23:59:59.000Z

44

Spin precession modulation in a magnetic bilayer  

SciTech Connect (OSTI)

We report on modulation of the spin precession in a Co/garnet bilayer by femtosecond laser excitation using time-resolved magneto-optical tools. Damped oscillations in the Faraday rotation transients representing precessional motion of the magnetization vector are observed in both the 2 nm Co layer and 1.8 {mu}m garnet of the bilayer with distinct frequencies differing by about a factor of two. The excitation efficiency of these precessions strongly depends on the out-of-plane magnetic field. The modulation effect with the coupling in a magnetic bilayer can be useful for non-thermally controlling the magnetization of nanomagnets and ultrafast switching in magnetic nanodevices.

Stupakiewicz, A.; Maziewski, A. [Laboratory of Magnetism, Faculty of Physics, University of Bialystok, Lipowa 41, Bialystok (Poland); Pashkevich, M. [Laboratory of Magnetism, Faculty of Physics, University of Bialystok, Lipowa 41, Bialystok (Poland); Scientific-Practical Materials Research Centre of the NASB, P. Brovki 19, Minsk (Belarus); Stognij, A.; Novitskii, N. [Scientific-Practical Materials Research Centre of the NASB, P. Brovki 19, Minsk (Belarus)

2012-12-24T23:59:59.000Z

45

Bilayer graphene quantum dot defined by topgates  

SciTech Connect (OSTI)

We investigate the application of nanoscale topgates on exfoliated bilayer graphene to define quantum dot devices. At temperatures below 500 mK, the conductance underneath the grounded gates is suppressed, which we attribute to nearest neighbour hopping and strain-induced piezoelectric fields. The gate-layout can thus be used to define resistive regions by tuning into the corresponding temperature range. We use this method to define a quantum dot structure in bilayer graphene showing Coulomb blockade oscillations consistent with the gate layout.

Müller, André; Kaestner, Bernd; Hohls, Frank; Weimann, Thomas; Pierz, Klaus; Schumacher, Hans W., E-mail: hans.w.schumacher@ptb.de [Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (Germany)

2014-06-21T23:59:59.000Z

46

Budding of domains in mixed bilayer membranes  

E-Print Network [OSTI]

We propose a model that accounts for budding behavior of domains in lipid bilayers, where each of the bilayer leaflets has a coupling between its local curvature and local lipid composition. The compositional asymmetry between the two monolayers leads to an overall spontaneous curvature. The membrane free-energy contains three contributions: bending energy, line tension, and a Landau free-energy for a lateral phase separation. Within a mean-field treatment, we obtain various phase diagrams which contain fully-budded, dimpled and flat states. In particular, for some range of membrane parameters, the phase diagrams exhibit a tricritical behavior as well as three-phase coexistence region. The global phase diagrams can be divided into three types and are analyzed in terms of the curvature-composition coupling parameter and domain size.

Wolff, Jean; Andelman, David

2014-01-01T23:59:59.000Z

47

Budding of domains in mixed bilayer membranes  

E-Print Network [OSTI]

We propose a model that accounts for budding behavior of domains in lipid bilayers, where each of the bilayer leaflets has a coupling between its local curvature and local lipid composition. The compositional asymmetry between the two monolayers leads to an overall spontaneous curvature. The membrane free-energy contains three contributions: bending energy, line tension, and a Landau free-energy for a lateral phase separation. Within a mean-field treatment, we obtain various phase diagrams which contain fully-budded, dimpled and flat states. In particular, for some range of membrane parameters, the phase diagrams exhibit a tricritical behavior as well as three-phase coexistence region. The global phase diagrams can be divided into three types and are analyzed in terms of the curvature-composition coupling parameter and domain size.

Jean Wolff; Shigeyuki Komura; David Andelman

2014-10-14T23:59:59.000Z

48

How Bilayer Graphene Got a Bandgap  

ScienceCinema (OSTI)

Graphene is the two-dimensional crystalline form of carbon, whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But theres a catch: graphene has no bandgap. Now Feng Wang and his colleagues at Berkeley Lab and UC Berkeley have engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 milli-electron volts, which is the energy of infrared radiation.

Feng Wang

2010-01-08T23:59:59.000Z

49

How Bilayer Graphene Got a Bandgap  

SciTech Connect (OSTI)

Graphene is the two-dimensional crystalline form of carbon, whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But theres a catch: graphene has no bandgap. Now Feng Wang and his colleagues at Berkeley Lab and UC Berkeley have engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 milli-electron volts, which is the energy of infrared radiation.

Feng Wang

2009-06-02T23:59:59.000Z

50

How Bilayer Graphene Got a Bandgap  

ScienceCinema (OSTI)

Graphene is the two-dimensional crystalline form of carbon, whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But theres a catch: graphene has no bandgap. Now Feng Wang and his colleagues at Berkeley Lab and UC Berkeley have engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 milli-electron volts, which is the energy of infrared radiation.

Wang, Feng

2013-05-29T23:59:59.000Z

51

Exciton and biexciton energies in bilayer systems  

Science Journals Connector (OSTI)

We report calculations of the energies of excitons and biexcitons in ideal two-dimensional bilayer systems within the effective-mass approximation with isotropic electron and hole masses. The exciton energies are obtained by a simple numerical integration technique, while the biexciton energies are obtained from diffusion quantum Monte Carlo calculations. The exciton binding energy decays as the inverse of the separation of the layers, while the binding energy of the biexciton with respect to dissociation into two separate excitons decays exponentially.

M. Y. J. Tan, N. D. Drummond, and R. J. Needs

2005-01-04T23:59:59.000Z

52

Tunable fractional quantum Hall phases in bilayer graphene  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Coulomb interactions drive the existence of a correlated many-body state. Bilayer graphene represents a particularly interesting material in which to study the fractional...

53

E-Print Network 3.0 - acid bilayers observed Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of Docosahexaenoic Acid-Containing Phospholipid Bilayers as Studied by 2H NMR... of vinyl perdeuterated arachidonic acid chains in bilayers of 1-palmitoyl-2-vinylperdeuterioara...

54

Landau-level dispersion and the quantum Hall plateaus in bilayer graphene  

SciTech Connect (OSTI)

We study the quantum Hall effect (QHE) in bilayer graphene using the Kubo-Greenwood formula. At zero temperature the Hall conductivity ?{sub yx} is given by ?{sub yx}?=?4(N+1)e{sup 2}/h with N the index of the highest occupied Landau level (LL). Including the dispersion of the LLs and their width, due to e.g. scattering by impurities, produces the plateau of the n = 0 LL in agreement with experimental results on doped samples and similar theoretical results on single-layer graphene plateaus widen with impurity concentration. Further, the evaluated resistivity ?{sub xx} exhibits a strong, oscillatory dependence on the electron concentration. Explicit results are obtained for ?-function impurities.

Zarenia, M.; Peeters, F. M. [Department of Physics, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium); Vasilopoulos, P.; Pourtolami, N. [Concordia University, Department of Physics, 7141 Sherbrooke Ouest, Montréal, Québec (Canada)

2013-12-04T23:59:59.000Z

55

Performance of Anode-Supported Solid Oxide Fuel Cell with Thin Bi-Layer Electrolyte by Pulsed Laser Deposition  

SciTech Connect (OSTI)

Anode-supported yttria stabilized zirconia (YSZ)/samaria doped ceria (SDC) bi-layer electrolytes with uniform thickness and high density were fabricated by pulsed laser deposition at 1000 degrees C. Fuel cells with such bi-layer electrolytes were fabricated and tested, yielding open circuit voltages from 0.94 to 1.0 V at 600-700 degrees C. Power densities from 0.4 to 1.0 W cm{sup -2} at 0.7 V were achieved in air at temperatures of 600-700 degrees C. Cell performance was improved in flowing oxygen, with an estimated peak power density of over 2 W cm{sup -2} at 650 degrees C, assuming the same overall resistance over the entire range of current density. The high cell performance was attributed to the very low ohmic resistance of the fuel cell, owing to the small thickness of the electrolyte. Stable performance was also demonstrated in that the voltage of the fuel cell showed very little change at a constant current density of 1 A cm{sup -2} during more than 400 hours of operation at 650 degrees C in flowing oxygen. SEM analysis of the fuel cell after testing showed that the bi-layer electrolyte had retained its chemical and mechanical integrity.

Lu, Zigui; Hardy, John S.; Templeton, Jared W.; Stevenson, Jeffry W.; Fisher, Daniel; Wu, Naijuan; Ignatiev, Alex

2012-07-15T23:59:59.000Z

56

Hot Carrier-Assisted Intrinsic Photoresponse in Graphene  

E-Print Network [OSTI]

We report on the intrinsic optoelectronic response of high-quality dual-gated monolayer and bilayer graphene p-n junction devices. Local laser excitation (of wavelength 850 nanometers) at the p-n interface leads to striking ...

Gabor, Nathaniel M.

57

Interfacial Widths of Conjugated Polymer Bilayers  

SciTech Connect (OSTI)

The interfaces of conjugated polyelectrolyte (CPE)/poly[2-methoxy-5-(2{prime}-ethylhexyloxy)-p-phenylene vinylene] (MEH-PPV) bilayers cast from differential solvents are shown by resonant soft X-ray reflectivity (RSoXR) to be very smooth and sharp. The chemical interdiffusion due to casting is limited to less than 0.6 nm, and the interface created is thus nearly 'molecularly' sharp. These results demonstrate for the first time and with high precision that the nonpolar MEH-PPV layer is not much disturbed by casting the CPE layer from a polar solvent. A baseline is established for understanding the role of interfacial structure in determining the performance of CPE-based polymer light-emitting diodes. More broadly, we anticipate further applications of RSoXR as an important tool in achieving a deeper understanding of other multilayer organic optoelectronic devices, including multilayer photovoltaic devices.

NCSU; UC Berkeley; UCSB; Advanced Light Source; Garcia, Andres; Yan, Hongping; Sohn, Karen E.; Hexemer, Alexander; Nguyen, Thuc-Quyen; Bazan, Guillermo C.; Kramer, Edward J.; Ade, Harald

2009-08-13T23:59:59.000Z

58

Chiral tunneling in single and bilayer graphene  

E-Print Network [OSTI]

We review chiral (Klein) tunneling in single-layer and bilayer graphene and present its semiclassical theory, including the Berry phase and the Maslov index. Peculiarities of the chiral tunneling are naturally explained in terms of classical phase space. In a one-dimensional geometry we reduced the original Dirac equation, describing the dynamics of charge carriers in the single layer graphene, to an effective Schr\\"odinger equation with a complex potential. This allowed us to study tunneling in details and obtain analytic formulas. Our predictions are compared with numerical results. We have also demonstrated that, for the case of asymmetric n-p-n junction in single layer graphene, there is total transmission for normal incidence only, side resonances are suppressed.

T. Tudorovskiy; K. J. A. Reijnders; M. I. Katsnelson

2011-06-15T23:59:59.000Z

59

Electrostatic and Magnetic Fields in Bilayer Graphene  

E-Print Network [OSTI]

We compute the transmission probability through rectangular potential barriers and p-n junctions in the presence of a magnetic and electric fields in bilayer graphene taking into account the full four bands of the energy spectrum. For energy E higher than the interlayer coupling $\\gamma_1 (E>\\gamma_1)$ two propagation modes are available for transport giving rise to four possible ways for transmission and reflection probabilities. However, when the energy is less then the height of the barrier the Dirac fermions exhibits transmission resonances and only one mode of propagation is available. We study the effect of the interlayer electrostatic potential $\\delta$ and the different geometry parameters of the barrier on the transmission probability.

Ahmed Jellal; Ilham Redouani; Hocine Bahlouli

2014-11-14T23:59:59.000Z

60

Excitons in intrinsic and bilayer graphene  

Science Journals Connector (OSTI)

Through first-principles calculations with many-body effects included, we have revealed unique excitonic effects in the high-frequency regime (10~20 eV) of optical spectra of graphene and bilayer graphene (BLG). Despite their different symmetries, the parallel ? and ?* bands result in enhanced excitonic effects in such two-dimensional (2-D) semimetals; one narrowly resonant exciton is discovered to form an isolated peak below the prominent absorption continuum with a surprisingly large binding energy; 270 meV in graphene and 80 meV in BLG. Moreover, because of its extremely weak resonant character, this exciton displays a bound electron-hole wave function and possesses a long intrinsic lifetime, which might be useful in designing optoelectronic applications of graphene.

Li Yang

2011-02-11T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Magnetism and pairing in Hubbard bilayers  

Science Journals Connector (OSTI)

We study the Hubbard model on a bilayer with repulsive on-site interactions U in which fermions undergo both intraplane (t) and interplane (tz) hopping. This situation is what one would expect in high-temperature superconductors such as YBa2Cu3O7-y, with two adjacent CuO2 planes. Magnetic and pairing properties of the system are investigated through quantum Monte Carlo simulations for both half- and quarter-filled bands. We find that in all cases interplanar pairing with dx2-z2 symmetry is dominant over planar pairing with dx2-y2 symmetry, and that for a large enough tz pair formation is possible through antiferromagnetic correlations. However, another mechanism is needed to make these pairs condense into a superconducting state at lower temperatures. We identify the temperature for pair formation with the spin-gap crossover temperature.

Raimundo R. dos Santos

1995-06-01T23:59:59.000Z

62

Bilayer-fish-scale ultrabroad terahertz bandpass filter  

Science Journals Connector (OSTI)

A bilayer fish-scale metamaterial is experimentally demonstrated to function as a broad bandpass filter in the terahertz regime. The measured 3 dB-bandwidth for normal incidence is...

Zhang, Xueqian; Gu, Jianqiang; Cao, Wei; Han, Jiaguang; Lakhtakia, Akhlesh; Zhang, Weili

2012-01-01T23:59:59.000Z

63

Quantum phases of dipolar bosons in bilayer geometry  

E-Print Network [OSTI]

We investigate the quantum phases of hard-core dipolar bosons confined to a square lattice in a bilayer geometry. Using exact theoretical techniques, we discuss the many-body effects resulting from the pairing of particles ...

Safavi-Naini, Arghavan

64

Bilayer Membrane in Confined Geometry: Interlayer Slide and Steric Repulsion  

E-Print Network [OSTI]

We derived free energy functional of a bilayer lipid membrane from the first principles of elasticity theory. The model explicitly includes position-dependent mutual slide of monolayers and bending deformation. Our free energy functional of liquid-crystalline membrane allows for incompressibility of the membrane and vanishing of the in-plane shear modulus and obeys reflectional and rotational symmetries of the flat bilayer. Interlayer slide at the mid-plane of the membrane results in local difference of surface densities of the monolayers. The slide amplitude directly enters free energy via the strain tensor. For small bending deformations the ratio between bending modulus and area compression coefficient, Kb/KA, is proportional to the square of monolayer thickness, h. Using the functional we performed self-consistent calculation of steric potential acting on bilayer between parallel confining walls separated by distance 2d. We found that temperature-dependent curvature at the minimum of confining potential is enhanced four times for a bilayer with slide as compared with a unit bilayer. We also calculate viscous modes of bilayer membrane between confining walls. Pure bending of the membrane is investigated, which is decoupled from area dilation at small amplitudes. Three sources of viscous dissipation are considered: water and membrane viscosities and interlayer drag. Dispersion has two branches. Confinement between the walls modifies the bending mode with respect to membrane in bulk solution. Simultaneously, inter-layer slipping mode, damped by viscous drag, remains unchanged by confinement.

S. V. Baoukina; S. I. Mukhin

2004-03-28T23:59:59.000Z

65

hal-00276997,version1-5May2008 Raman spectra of misoriented bilayer graphene  

E-Print Network [OSTI]

hal-00276997,version1-5May2008 Raman spectra of misoriented bilayer graphene P. Poncharal1 , A layer graphene with a bilayer in which the two layers are arbitrarily misoriented. The profiles of the 2 of the electronic structures of single layer graphene and misoriented bilayer graphene. Another new aspect

66

Inversion kinetics for Kr-Xe bilayers on palladium  

Science Journals Connector (OSTI)

The thermally activated inversion of Kr-Xe bilayers on Pd is studied with the use of photoemission and photon-excited Auger spectroscopy. Bilayers formed by the deposit of a monolayer or less of Xe on top of a monolayer of Kr on Pd at 49 K are shown to invert when the temperature is raised, with Xe coming in direct contact with the substrate. For a Pd(111) substrate the activation energy of this inversion process is determined: Ea=0.12±0.03 eV.

G. Kaindl; T.-C. Chiang; D. E. Eastman

1982-06-15T23:59:59.000Z

67

Graphene Monolayer Rotation on Ni(111) Facilities Bilayer Graphene Growth  

SciTech Connect (OSTI)

Synthesis of bilayer graphene by chemical vapor deposition is of importance for graphene-based field effect devices. Here, we demonstrate that bilayer graphene preferentially grows by carbon-segregation under graphene sheets that are rotated relative to a Ni(111) substrate. Rotated graphene monolayer films can be synthesized at growth temperatures above 650 C on a Ni(111) thin-film. The segregated second graphene layer is in registry with the Ni(111) substrate and this suppresses further C-segregation, effectively self-limiting graphene formation to two layers.

Batzill M.; Sutter P.; Dahal, A.; Addou, R.

2012-06-11T23:59:59.000Z

68

Surface tension in bilayer membranes with fixed projected area  

E-Print Network [OSTI]

We study the elastic response of bilayer membranes with fixed projected area to both stretching and shape deformations. A surface tension is associated to each of these deformations. By using model amphiphilic membranes and computer simulations, we are able to observe both the types of deformation, and thus, both the surface tensions, related to each type of deformation, are measured for the same system. These surface tensions are found to assume different values in the same bilayer membrane: in particular they vanish for different values of the projected area. We introduce a simple theory which relates the two quantities and successfully apply it to the data obtained with computer simulations.

Alberto Imparato

2006-04-05T23:59:59.000Z

69

Random-Gap Model for Graphene and Graphene Bilayers  

Science Journals Connector (OSTI)

The effect of a randomly fluctuating gap, created by a random staggered potential, is studied in a monolayer and a bilayer of graphene. The density of states, the one-particle scattering rate, and the transport properties (diffusion coefficient and conductivity) are calculated at the neutrality point. All of these quantities vanish at a critical value of the average staggered potential, signaling a continuous transition to an insulating behavior. Transport quantities are directly linked to the one-particle scattering rate. Although the behavior is qualitatively the same in mono- and bilayers, the effect of disorder is much stronger in the latter.

K. Ziegler

2009-03-24T23:59:59.000Z

70

Electronic band structure of magnetic bilayer graphene superlattices  

SciTech Connect (OSTI)

Electronic band structure of the bilayer graphene superlattices with ?-function magnetic barriers and zero average magnetic flux is studied within the four-band continuum model, using the transfer matrix method. The periodic magnetic potential effects on the zero-energy touching point between the lowest conduction and the highest valence minibands of pristine bilayer graphene are exactly analyzed. Magnetic potential is shown also to generate the finite-energy touching points between higher minibands at the edges of Brillouin zone. The positions of these points and the related dispersions are determined in the case of symmetric potentials.

Pham, C. Huy; Nguyen, T. Thuong [Theoretical and Computational Physics Department, Institute of Physics, VAST, 10 Dao Tan, Ba Dinh Distr., Hanoi 10000 (Viet Nam); SISSA/International School for Advanced Study, Via Bonomea 265, I-34136 Trieste (Italy); Nguyen, V. Lien, E-mail: nvlien@iop.vast.ac.vn [Theoretical and Computational Physics Department, Institute of Physics, VAST, 10 Dao Tan, Ba Dinh Distr., Hanoi 10000 (Viet Nam); Institute for Bio-Medical Physics, 109A Pasteur, 1st Distr., Hochiminh City (Viet Nam)

2014-09-28T23:59:59.000Z

71

Registered and antiregistered phase separation of mixed amphiphilic bilayers  

E-Print Network [OSTI]

We derive a mean-field free energy for phase separation in coupled bilayer leaflets. Our model accounts for amphiphile-level structure, in particular hydrophobic mismatch, which promotes $\\textit{antiregistration}$ (AR), in competition with the `direct' trans-midplane coupling usually studied, promoting registration (R). For phospholipid parameters equilibrium demixing is typically R, but hydrophobic mismatch favours metastable AR phases, which can cause a bilayer in the `spinodal region' to require nucleation in order to equilibrate. This provides a framework for understanding existing observations, elucidating a subtle, often overlooked competition of couplings, and a key role for phase transition kinetics in determining domain registration/antiregistration.

John J. Williamson; Peter D. Olmsted

2014-08-12T23:59:59.000Z

72

The component groups structure of DPPC bilayers obtained by specular neutron reflectometry  

E-Print Network [OSTI]

Specular neutron reflectometry (SNR) was measured on a system of a floating bilayer consisting of 1,2-dipalmitoyl-d62-\\textit{sn}-glycero-3-phosphocholine (d62-diC16:0PC) deposited over a 1,2-dibehenoyl-\\textit{sn}-glycero-3-phosphocholine (diC22:0PC) bilayer at 25 and 55 {\\deg}C. The internal structure of lipid bilayers was described by a one dimensional scattering length density profile (SLDP) model, originally developed for the evaluation of small angle scattering data. The corresponding model reflectivity curves successfully describe the experimental reflectivity curves of a supported bilayer in the gel phase and a system of a floating bilayer in the liquid crystalline phase. The reflectivity data from the supported bilayer were evaluated individually and served further as an input by the data treatment of floating bilayer reflectivity curves. The results yield internal structure of a deposited and floating bilayer on the level of component groups of lipid molecules. The obtained structure of the floating d62-diC16:0PC bilayer displays high resemblance to the bilayer structure in the form of unilamellar vesicles, however, simultaneously it shows rate of fluctuations in comparison to unilamellar vesicle bilayers.

Michal Beli?ka; Yuri Gerelli; Norbert Ku?erka; Giovanna Fragneto

2014-12-16T23:59:59.000Z

73

Evaporation-Induced Buckling and Fission of Microscale Droplet Interface Bilayers  

SciTech Connect (OSTI)

Droplet interface bilayers (DIBs) are a robust platform for studying synthetic cellular membranes; however, to date no DIBs have been produced at cellular length scales. Here, we create microscale droplet interface bilayers ( DIBs) at the interface between aqueous femtoliter-volume droplets within an oil-filled microfluidic channel. The uniquely large area-to-volume ratio of the droplets results in strong evaporation effects, causing the system to transition through three distinct regimes. First, the two adjacent droplets shrink into the shape of a single spherical droplet, where an augmented lipid bilayer partitions two hemi-spherical volumes. In the second regime, the combined effects of the shrinking monolayers and growing bilayer force the confined bilayer to buckle to conserve its mass. Finally, at a bending moment corresponding to a critical shear stress, the buckling bilayer fissions a vesicle to regulate its shape and stress. The DIBs produced here enable evaporation-induced bilayer dynamics reminiscent of endo- and exocytosis in cells.

Boreyko, Jonathan B [ORNL; Mruetusatorn, Prachya [ORNL; Sarles, Stephen A [ORNL; Retterer, Scott T [ORNL; Collier, Pat [ORNL

2013-01-01T23:59:59.000Z

74

Topological insulating phases in mono and bilayer graphene  

E-Print Network [OSTI]

We analyze the influence of different quadratic interactions giving rise to time reversal invariant topological insulating phases in mono and bilayer graphene. We make use of the effective action formalism to determine the dependence of the Chern Simons coefficient on the different interactions.

Alberto Cortijo; Adolfo G. Grushin; Maria A. H. Vozmediano

2010-07-21T23:59:59.000Z

75

Quantum theory of bilayer quantum Hall smectics Emiliano Papa,1  

E-Print Network [OSTI]

of charge-density and position along each stripe edge. The soft modes associated with the broken symmetries spontaneous interlayer phase coherence and a sizable charge gap even at relatively large layer separations in very high mobility bilayer systems at dilution refrigerator temperatures as a function of layer

76

Effect of cholesterol on diffusion in surfactant bilayers Thorsten Piepera  

E-Print Network [OSTI]

2007 Biological membranes consist of lipid bilayers with liquid-ordered and liquid-disordered phases the choles- terol and lipid contents of the membrane play an important role for the regulation of protein provide high pre- cision due to averaging over large ensembles of particles. On the other hand, when

Suter, Dieter

77

Molecular friction and epitactic coupling between monolayers in supported bilayers  

E-Print Network [OSTI]

1535 Molecular friction and epitactic coupling between monolayers in supported bilayers R. Merkel un substrat de membrane couplée (Evans et Sackmann, 1988), on détermine la friction moléculaire coefficients de friction entre les couches en fixant la couche mononucléaire proximale sur le substrat par des

Boyer, Edmond

78

Berry phase and pseudospin winding number in bilayer graphene  

E-Print Network [OSTI]

Ever since the novel quantum Hall effect in bilayer graphene was discovered, and explained by a Berry phase of 2? [ K. S. Novoselov et al. Nat. Phys. 2 177 (2006)], it has been widely accepted that the low-energy electronic ...

Marzari, Nicola

79

Josephson inplane and tunneling currents in bilayer quantum Hall system  

SciTech Connect (OSTI)

A Bose-Einstein condensation is formed by composite bosons in the quantum Hall state. A composite boson carries the fundamental charge (–e). We investigate Josephson tunneling of such charges in the bilayer quantum Hall system at the total filling ? = 1. We show the existence of the critical current for the tunneling current to be coherent and dissipationless in tunneling experiments with various geometries.

Ezawa, Z. F. [Nishina Center, RIKEN, Saitama 351-0198 (Japan); Tsitsishvili, G. [Georgia Department of Physics, Tbilisi State University, Tbilisi 0179 (Georgia); Sawada, A. [Research Center for Low Temperature and Materials Sciences, Kyoto University, Kyoto 606-8501 (Japan)

2013-12-04T23:59:59.000Z

80

Stacking-dependent electronic structure of bilayer silicene  

SciTech Connect (OSTI)

Bilayer silicene (BLS) is a class of material that possibly holds both topological and superconducting properties; however, its structure is not fully understood. By scanning stacking modes and lattice constants using first principles calculations, several meta-stable configurations are identified, including a slightly faulted-AA packing structure, named slide-2AA. Different from the metallic properties of conventional AA and AB stacking forms, band structure of slide-2AA bilayer presents a sizeable indirect energy gap of ?1.16?eV. A metal-semiconductor phase transition along the sliding pathway with a small energy barrier is also observed, indicating its electronic properties can be easily tuned by applying small shear force along the BLS surface plane. Such unique quantitative relationship of structure and electronic properties has profound implications in nanoelectronics and electromechanical devices.

Fu, Huixia; Zhang, Jin; Ding, Zijing; Li, Hui, E-mail: huili8@iphy.ac.cn, E-mail: smeng@iphy.ac.cn; Meng, Sheng, E-mail: huili8@iphy.ac.cn, E-mail: smeng@iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2014-03-31T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Band Tunneling through Double Barrier in Bilayer Graphene  

E-Print Network [OSTI]

By taking into account the full four band energy spectrum, we calculate the transmission probability and conductance of electrons across symmetric and asymmetric double potential barrier with a confined interlayer potential difference in bilayer graphene. For energies less than the interlayer coupling \\gamma_{1}, E \\gamma_{1}, we obtain four possible ways for transmission resulting from the two propagating modes. We compute the associated transmission probabilities as well as their contribution to the conductance, study the effect of the double barrier geometry.

Hasan A. Alshehab; Hocine Bahlouli; Abderrahim El Mouhafid; Ahmed Jellal

2014-01-20T23:59:59.000Z

82

Synthesis and Electrical Characterization of Magnetic Bilayer Graphene Intercalate  

Science Journals Connector (OSTI)

Synthesis and Electrical Characterization of Magnetic Bilayer Graphene Intercalate ... § Center for Superfunctional Materials, Department of Chemistry and Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea ... This work was supported by NRF (National Scientist Program, GRL, EPB Center, 2009-0063312; WCU, R32-2008-000-10180-0), the AFOSR0MURI, FENA, and DARPA CERA, and DOE (DE-FG02-05ER46215). ...

Namdong Kim; Kwang S. Kim; Naeyoung Jung; Louis Brus; Philip Kim

2011-01-26T23:59:59.000Z

83

Fast Membranes Hemifusion via Dewetting between Lipid Bilayers  

E-Print Network [OSTI]

The behavior of lipid bilayer is important to understand the functionality of cells like the trafficking of ions between cells. Standard procedures to explore the properties of lipid bilayer and hemifused states typically use either supported membranes or vesicles. Both techniques have several shortcoming in terms of bio relevance or accessibility for measurements. In this article the formation of individual free standing hemifused states between model cell membranes is studied using an optimized microfluidic scheme which allows for simultaneous optical and electrophysiological measurements. In a first step, two model membranes are formed at a desired location within a microfluidic device using a variation of the droplet interface bilayer (DiB) technique. In a second step, the two model membranes are brought into contact forming a single hemifused state. For all tested lipids, the hemifused state between free standing membranes form within hundreds of milliseconds, i.e. several orders of magnitude faster than reported in literature. The formation of a hemifused state is observed as a two stage process, whereas the second stage can be explained as a dewetting process in no-slip boundary condition. The formed hemifusion states are long living and a single fusion event can be observed when triggered by an applied electric field as demonstrated for monoolein.

Jose Nabor Vargas; Ralf Seemann; Jean-Baptiste Fleury

2014-09-20T23:59:59.000Z

84

Title: Electron-Hole Asymmetric Integer and Fractional Quantum Hall Effect in Bilayer Graphene  

E-Print Network [OSTI]

Title: Electron-Hole Asymmetric Integer and Fractional Quantum Hall Effect in Bilayer Graphene graphene is predicted to pro- duce novel and tunable FQH ground states. Here we present local electronic compressibility measurements of the FQH effect in the lowest Landau level of bilayer graphene. We observe

Yacoby, Amir

85

Hollow structures with bilayer graphene walls Peter J.F. Harris *  

E-Print Network [OSTI]

Hollow structures with bilayer graphene walls Peter J.F. Harris * Centre for Advanced Microscopy, J.J. Thomson Physical Laboratory, University of Reading, Whiteknights, Reading RG6 6AF, UK A R T I C L E I N F A B S T R A C T The formation of three-dimensional shell-like structures with bilayer graphene walls

Harris, Peter J F

86

Development of a Microfluidic Device for Synthesis of Lipid Bi-Layer In-Situ  

E-Print Network [OSTI]

and result in unstable bi-layers having a short lifetime. In this investigation a novel microfluidic device and a method for artificial synthesis of lipid bi-layer in-situ are explored. In the proposed method, lipid trapped at an aperture on a Teflon sheet...

Banneyake, Bm U.

2010-01-14T23:59:59.000Z

87

Carrier scattering, mobilities, and electrostatic potential in monolayer, bilayer, and trilayer graphene  

E-Print Network [OSTI]

graphene Wenjuan Zhu,* Vasili Perebeinos, Marcus Freitag, and Phaedon Avouris IBM Thomas J. Watson Research mobility in monolayer, bilayer, and trilayer graphene has been systematically studied. We found that as the carrier density increases, the mobility decreases for monolayer graphene, while it increases for bilayer

Perebeinos, Vasili

88

Lipid Bilayer Structure Determined by the Simultaneous Analysis of Neutron and X-Ray Scattering Data  

E-Print Network [OSTI]

Lipid Bilayer Structure Determined by the Simultaneous Analysis of Neutron and X-Ray Scattering) and dipalmitoylphosphatidylcholine (DPPC) bilayers by simultaneously analyzing x-ray and neutron scattering data. The neutron data electron and neutron scattering density profiles. A key result of the analysis is the molecular surface

Nagle, John F.

89

Production of microporous aluminum oxide electrodes as supports for tethered lipid bilayers of large surface area.  

E-Print Network [OSTI]

1 Production of microporous aluminum oxide electrodes as supports for tethered lipid bilayers.Bourdillon@utc.fr Abstract A composite electrode made by association of gold and porous aluminum oxide has been used aluminum oxide; phospholipid bilayer; two-dimensional electrochemistry; ubiquinone lateral mobility. 1

Paris-Sud XI, Université de

90

Crystalline silicon growth in nickel/a-silicon bilayer  

SciTech Connect (OSTI)

The effect of substrate temperature on amorphous Silicon crystallization, mediated by metal impurity is reported. Bilayers of Ni(200nm)/Si(400nm) are deposited on fused silica substrate by electron beam evaporator at 200 and 500 Degree-Sign C. Raman mapping shows that, 2 to 5 micron size crystalline silicon clusters are distributed over the entire surface of the sample. X-ray diffraction and X-ray absorption spectroscopy studies demonstrate silicon crystallizes over the metal silicide seeds and grow with the annealing temperature.

Mohiddon, Md Ahamad; Naidu, K. Lakshun [School of Physics, University of Hyderabad, Hyderabad-500046 (India) and Department of Physics, University of Trento, 38123 POVO (Trento) (Italy); Dalba, G. [Department of Physics, University of Trento, 38123 POVO (Trento) (Italy); Rocca, F. [IFN-CNR, Institute for Photonics and Nanotechnologies, Unit FBK-Photonics of Trento, 38123, Trento (Italy); Krishna, M. Ghanashyam [School of Physics, University of Hyderabad, Hyderabad-500046 (India)

2013-02-05T23:59:59.000Z

91

Two-Stage Magnetization Reversal in Exchange Biased Bilayers  

SciTech Connect (OSTI)

MnF{sub 2}/Fe bilayers exhibit asymmetric magnetization reversal that occurs by coherent rotation on one side of the loop and by nucleation and propagation of domain walls on the other side of the loop. Here, we show by polarized neutron reflectometry, magnetization, and magnetotransport measurements that for samples with good crystalline ''quality'' the rotation is a two-stage process, due to coherent rotation to a stable state perpendicular to the cooling field direction. The result is remarkably asymmetrically shaped hysteresis loops.

Leighton, C.; Fitzsimmons, M. R.; Yashar, P.; Hoffmann, A.; Nogues, J.; Dura, J.; Majkrzak, C. F.; Schuller, Ivan K.

2001-05-07T23:59:59.000Z

92

Electron-doping  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Electron-doping Electron-doping evolution of the low-energy spin excitations in the iron arsenide superconductor BaFe 2-x Ni x As 2 Miaoyin Wang, 1 Huiqian Luo, 2 Jun Zhao, 1 Chenglin Zhang, 1 Meng Wang, 2,1 Karol Marty, 3 Songxue Chi, 4 Jeffrey W. Lynn, 4 Astrid Schneidewind, 5,6 Shiliang Li, 2, * and Pengcheng Dai 1,2,3,† 1 Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996-1200, USA 2 Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China 3 Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6393, USA 4 NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA 5 Gemeinsame Forschergruppe HZB, Helmholtz-Zentrum Berlin für Materialien und Energie, D-14109

93

The Molecular Structure of a Phosphatidylserine Bilayer Determined by Scattering and Molecular Dynamics Simulations  

SciTech Connect (OSTI)

Phosphatidylserine (PS) lipids play essential roles in biological processes, including enzyme activation and apoptosis. We report on the molecular structure and atomic scale interactions of a fluid bilayer composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylserine (POPS). A scattering density profile model, aided by molecular dynamics (MD) simulations, was developed to jointly refine different contrast small-angle neutron and X-ray scattering data, which yielded a lipid area of 62.7 A2 at 25 C. MD simulations with POPS lipid area constrained at different values were also performed using all-atom and aliphatic united-atom models. The optimal simulated bilayer was obtained using a model-free comparison approach. Examination of the simulated bilayer, which agrees best with the experimental scattering data, reveals a preferential interaction between Na+ ions and the terminal serine and phosphate moieties. Long-range inter-lipid interactions were identified, primarily between the positively charged ammonium, and the negatively charged carboxylic and phosphate oxygens. The area compressibility modulus KA of the POPS bilayer was derived by quantifying lipid area as a function of surface tension from area-constrained MD simulations. It was found that POPS bilayers possess a much larger KA than that of neutral phosphatidylcholine lipid bilayers. We propose that the unique molecular features of POPS bilayers may play an important role in certain physiological functions.

Pan, Jianjun [University of South Florida, Tampa (USF)] [University of South Florida, Tampa (USF); Cheng, Xiaolin [ORNL] [ORNL; Monticelli, Luca [Institut National de la Santé et de la Recherche Médicale (INSERM) and INTS, France] [Institut National de la Santé et de la Recherche Médicale (INSERM) and INTS, France; Heberle, Frederick A [ORNL] [ORNL; Kucerka, Norbert [Atomic Energy of Canada Limited (AECL), Canadian Neutron Beam Centre (CNBC) and Comenius University,] [Atomic Energy of Canada Limited (AECL), Canadian Neutron Beam Centre (CNBC) and Comenius University,; Tieleman, D. Peter [University of Calgary, ALberta, Canada] [University of Calgary, ALberta, Canada; Katsaras, John [ORNL] [ORNL

2014-01-01T23:59:59.000Z

94

Passivating overcoat bilayer for multilayer reflective coatings for extreme ultraviolet lithography  

DOE Patents [OSTI]

A passivating overcoat bilayer is used for multilayer reflective coatings for extreme ultraviolet (EUV) or soft x-ray applications to prevent oxidation and corrosion of the multilayer coating, thereby improving the EUV optical performance. The overcoat bilayer comprises a layer of silicon or beryllium underneath at least one top layer of an elemental or a compound material that resists oxidation and corrosion. Materials for the top layer include carbon, palladium, carbides, borides, nitrides, and oxides. The thicknesses of the two layers that make up the overcoat bilayer are optimized to produce the highest reflectance at the wavelength range of operation. Protective overcoat systems comprising three or more layers are also possible.

Montcalm, Claude (Livermore, CA); Stearns, Daniel G. (Los Altos, CA); Vernon, Stephen P. (Pleasanton, CA)

1999-01-01T23:59:59.000Z

95

Ag and Au atoms intercalated in bilayer heterostructures of transition metal dichalcogenides and graphene  

SciTech Connect (OSTI)

The diffusive motion of metal nanoparticles Au and Ag on monolayer and between bilayer heterostructures of transition metal dichalcogenides and graphene are investigated in the framework of density functional theory. We found that the minimum energy barriers for diffusion and the possibility of cluster formation depend strongly on both the type of nanoparticle and the type of monolayers and bilayers. Moreover, the tendency to form clusters of Ag and Au can be tuned by creating various bilayers. Tunability of the diffusion characteristics of adatoms in van der Waals heterostructures holds promise for controllable growth of nanostructures.

Iyikanat, F., E-mail: fadiliyikanat@iyte.edu.tr; Senger, R. T. [Department of Physics, Izmir Institute of Technology, 35430 Izmir (Turkey); Sahin, H., E-mail: hasan.sahin@uantwerpen.be; Peeters, F. M. [Department of Physics, University of Antwerp, 2610 Antwerp (Belgium)

2014-09-01T23:59:59.000Z

96

Realization of free-standing silicene using bilayer graphene  

SciTech Connect (OSTI)

The available synthesized silicene-like structures have been only realized on metallic substrates which are very different from the standalone buckled silicene, e.g., the Dirac cone of silicene is destroyed due to lattice distortion and the interaction with the substrate. Using graphene bilayer as a scaffold, a route is proposed to synthesize silicene with electronic properties decoupled from the substrate. The buckled hexagonal arrangement of silicene between the graphene layers is found to be very similar to the theoretically predicted standalone buckled silicene which is only very weakly van der Waals coupled to the graphene layers with a graphite-like interlayer distance of 3.42?Å and without any lattice distortion. We found that these stacked layers are stable well above room temperature.

Neek-Amal, M. [Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium) [Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium); Department of Physics, Shahid Rajaee Teacher Training University, Lavizan, Tehran 16785-136 (Iran, Islamic Republic of); Sadeghi, A. [Department of Physics, Basel University, Klingelbergestrasse 82, CH-4056 Basel (Switzerland)] [Department of Physics, Basel University, Klingelbergestrasse 82, CH-4056 Basel (Switzerland); Berdiyorov, G. R.; Peeters, F. M. [Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium)] [Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium)

2013-12-23T23:59:59.000Z

97

Independent Manipulation of Electric and Thermal Fields with Bilayer Structure  

E-Print Network [OSTI]

Recently, increasing attention has been focused on the employment of transformation and metamaterial for manipulation of various physical fields, which requires complicated configuration and usually limits in single field. Here, for the first time, we propose and experimentally demonstrated bilayer structure to achieve simultaneously independent manipulation of multi-physics field (dc electric fields and thermal) by directly solving the dc electric/ thermal field equations. This structure is composed of two layers: the outer layer is made of isotropic and homogeneous material, while the inner layer is fan-shape layer. Since it is not based on TO, it can be readily experimentally fabricated with naturally occurring materials. Experimentally, we has designed, fabricated and characterized two structures simultaneously behaving as dc electric cloak/ thermal concentrator and dc electric concentrator/ thermal cloak, respectively. The simulation results agree well with the experiment ones, thus confirming the feasib...

Lan, Chuwen; Wu, Lingling; Li, Bo; Zhou, Ji

2015-01-01T23:59:59.000Z

98

Cooling of cryogenic electron bilayers via the Coulomb interaction  

E-Print Network [OSTI]

Heat dissipation in current-carrying cryogenic nanostructures is problematic because the phonon density of states decreases strongly as energy decreases. We show that the Coulomb interaction can prove a valuable resource for carrier cooling via coupling to a nearby, cold electron reservoir. Specifically, we consider the geometry of an electron bilayer in a silicon-based heterostructure, and analyze the power transfer. We show that across a range of temperatures, separations, and sheet densities, the electron-electron interaction dominates the phonon heat-dissipation modes as the main cooling mechanism. Coulomb cooling is most effective at low densities, when phonon cooling is least effective in silicon, making it especially relevant for experiments attempting to perform coherent manipulations of single spins.

John King Gamble; Mark Friesen; Robert Joynt; S. N. Coppersmith

2011-04-13T23:59:59.000Z

99

Axially Tapered And Bilayer Microchannels For Evaporative Cooling Devices  

DOE Patents [OSTI]

The invention consists of an evaporative cooling device comprising one or more microchannels whose cross section is axially reduced to control the maximum capillary pressure differential between liquid and vapor phases. In one embodiment, the evaporation channels have a rectangular cross section that is reduced in width along a flow path. In another embodiment, channels of fixed width are patterned with an array of microfabricated post-like features such that the feature size and spacing are gradually reduced along the flow path. Other embodiments incorporate bilayer channels consisting of an upper cover plate having a pattern of slots or holes of axially decreasing size and a lower fluid flow layer having channel widths substantially greater than the characteristic microscale dimensions of the patterned cover plate. The small dimensions of the cover plate holes afford large capillary pressure differentials while the larger dimensions of the lower region reduce viscous flow resistance.

Nilson, Robert (Cardiff, CA); Griffiths, Stewart (Livermore, CA)

2005-10-04T23:59:59.000Z

100

Unraveling the interlayer-related phonon self-energy renormalization in bilayer graphene  

E-Print Network [OSTI]

In this letter, we present a step towards understanding the bilayer graphene (2LG) interlayer (IL)-related phonon combination modes and overtones as well as their phonon self-energy renormalizations by using both gate-modulated ...

Araujo, Paulo Antonio Trinidade

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101

Phase diagram and phase transitions of monolayer and bilayer CF4 on graphite  

Science Journals Connector (OSTI)

The phase diagram of CF4 adsorbed on graphite in the monolayer and bilayer region is mapped out in an ac heat-capacity study. In the monolayer region, the resultant phase diagram shows the existence of five different solid phases. The melting transition can proceed from the (2×2) commensurate, I(S) (an incommensurate phase), and the hexagonal incommensurate (HI) phases. Strongly-first-order melting is found from the (2×2) and the I(S) phases. In contrast, a sharp and small heat-capacity peak followed by a broad anomaly, similar to the melting of Ar on graphite in the submonolayer region, is observed at the melting of the HI phase. In the bilayer region, four different regions of coexisting solid phases are found. The melting of the bilayer solid occurs at a triple point at 89.05 K. Our data also suggest a bilayer critical point at 93 K.

Q. M. Zhang; H. K. Kim; M. H. W. Chan

1986-12-01T23:59:59.000Z

102

Ca intercalated bilayer graphene as a thinnest limit of superconducting C6Ca  

Science Journals Connector (OSTI)

...superconductivity and rechargeable batteries. It is thus quite challenging...intercalated bilayer graphene, and to investigate...useful in fabricating graphene-based nanodevices...devices, ultrathin battery and microchemical catalysis...Thus, intercalated graphene provides a promising...

Kohei Kanetani; Katsuaki Sugawara; Takafumi Sato; Ryota Shimizu; Katsuya Iwaya; Taro Hitosugi; Takashi Takahashi

2012-01-01T23:59:59.000Z

103

Debonding in bi-layer material systems under moisture effect : a multiscale approach  

E-Print Network [OSTI]

Bi-layer material systems are found in various engineering applications ranging from nano-scale components, such as thin films in circuit boards, to macro-scale structures such as adhesive bonding in aerospace and civil ...

Lau, Tak-bun, Denvid

2012-01-01T23:59:59.000Z

104

Bilayer graphene growth by low pressure chemical vapor deposition on copper foil  

E-Print Network [OSTI]

Successfully integrating graphene in standard processes for applications in electronics relies on the synthesis of high-quality films. In this work we study Low Pressure Chemical Vapor Deposition (LPCVD) growth of bilayer ...

Fang, Wenjing, S.M. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

105

Zone folding effect in Raman G-band intensity of twisted bilayer graphene  

E-Print Network [OSTI]

The G-band Raman intensity is calculated for twisted bilayer graphene as a function of laser excitation energy based on the extended tight binding method. Here we explicitly consider the electron-photon and electron-phonon ...

Dresselhaus, Mildred

106

Effects of Carbon Nanotubes in Barrier Epithelial Cells via Effects on Lipid Bilayers Shanta Lewis1  

E-Print Network [OSTI]

Effects of Carbon Nanotubes in Barrier Epithelial Cells via Effects on Lipid Bilayers Shanta Lewis1 Physiology, IU School of Medicine Carbon nanotubes (CNTs) are one of many nanoparticles (NP) which are being

Zhou, Yaoqi

107

Study of magnetic configurations in exchange-coupled bilayers by polarized neutron reflectometry  

Science Journals Connector (OSTI)

The magnetic configurations of exchange-coupled bilayers Gd40Fe60/TbXFe1-X were investigated by SQUID magnetometry and polarized neutron reflectometry (PNR). Depending on the composition of...

S. Mangin; F. Montaigne; C. Bellouard; H. Fritzsche

2002-12-01T23:59:59.000Z

108

Correlation effects in (111) bilayers of perovskite transition-metal oxides  

SciTech Connect (OSTI)

We investigate the correlation-induced Mott, magnetic, and topological phase transitions in artificial (111) bilayers of perovskite transition-metal oxides LaAuO3 and SrIrO3 for which the previous density-functional theory calculations predicted topological insulating states. Using the dynamical-mean-field theory with realistic band structures and Coulomb interactions, LaAuO3 bilayer is shown to be far away from a Mott insulating regime, and a topological-insulating state is robust. On the other hand, SrIrO3 bilayer is on the verge of an orbital-selective topological Mott transition and turns to a trivial insulator by an antiferromagnetic ordering. Oxide bilayers thus provide a novel class of topological materials for which the interplay between the spin-orbit coupling and electron-electron interactions is a fundamental ingredient.

Okamoto, Satoshi [ORNL] [ORNL; Zhu, Wenguang [University of Science and Technology of China] [University of Science and Technology of China; Nomura, Yusuke [University of Tokyo, Japan] [University of Tokyo, Japan; Arita, R. [University of Tokyo, Japan] [University of Tokyo, Japan; Xiao, Di [Carnegie Mellon University (CMU)] [Carnegie Mellon University (CMU); Nagaosa, Naoto [University of Tokyo, Japan] [University of Tokyo, Japan

2014-01-01T23:59:59.000Z

109

Doping of gallium nitride using disilane  

Science Journals Connector (OSTI)

Keywords: disilane, gallium nitride, metalorganic chemical vapor deposition, organometallic vapor phase epitaxy, silicon doping

A. E. Wickenden; L. B. Rowland; K. Doverspike; D. K. Gaskill; J. A. Freitas, Jr.; D. S. Simons; P. H. Chi

1995-11-01T23:59:59.000Z

110

Nitrogen-Doped Graphene and its Application in Electrochemical...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Doped Graphene and its Application in Electrochemical Biosensing. Nitrogen-Doped Graphene and its Application in Electrochemical Biosensing. Abstract: Chemical doping with foreign...

111

Nitrogen-doped Graphene and Its Electrochemical Applications...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

doped Graphene and Its Electrochemical Applications. Nitrogen-doped Graphene and Its Electrochemical Applications. Abstract: Nitrogen-doped graphene (N-graphene) is obtained by...

112

Ideal strength of doped graphene  

Science Journals Connector (OSTI)

While the mechanical distortions change the electronic properties of graphene significantly, the effects of electronic manipulation on its mechanical properties have not been known. Using first-principles calculation methods, we show that when graphene expands isotropically under equibiaxial strain, both the electron and hole doping can maintain or improve its ideal strength slightly and enhance the critical breaking strain dramatically. Contrary to the isotropic expansions, the electron doping decreases the ideal strength as well as critical strain of uniaxially strained graphene while the hole doping increases both. Distinct failure mechanisms depending on type of strains are shown to be origins of the different doping induced mechanical stabilities. Our findings may resolve a contradiction between recent experimental and theoretical results on the strength of graphene.

S. J. Woo and Young-Woo Son

2013-02-13T23:59:59.000Z

113

Indium doped zinc oxide nanowire thin films for antireflection and solar absorber coating applications  

SciTech Connect (OSTI)

Indium doped ZnO nanowire thin films were prepared by thermal oxidation of Zn-In metal bilayer films at 500°C. The ZnO:In nanowires are 20-100 nm in diameter and several tens of microns long. X-ray diffraction patterns confirm the formation of oxide and indicate that the films are polycrystalline, both in the as deposited and annealed states. The transmission which is <2% for the as deposited Zn-In films increases to >90% for the ZnO:In nanowire films. Significantly, the reflectance for the as deposited films is < 10% in the region between 200 to 1500 nm and < 2% for the nanowire films. Thus, the as deposited films can be used solar absorber coatings while the nanowire films are useful for antireflection applications. The growth of nanowires by this technique is attractive since it does not involve very high temperatures and the use of catalysts.

Shaik, Ummar Pasha [ACRHEM, University of Hyderabad, Hyderabad-500046 (India); Krishna, M. Ghanashyam, E-mail: mgksp@uohyd.ac.in [ACRHEM and School of Physics, University of Hyderabad, Hyderabad-500046 (India)

2014-04-24T23:59:59.000Z

114

A p ? n transition for Sn-doped Cu(In,Ga)Se{sub 2} bulk materials  

SciTech Connect (OSTI)

Cu(In,Ga)Se{sub 2} (CIGSe) pellets at different Sn contents were fabricated by reactive liquid-phase sintering at 600–700 °C with the help of sintering aids of Sb{sub 2}S{sub 3} and Te. Powder preparation was based upon the molecular formula of Cu{sub 0.9}[(In{sub 0.7?x}Sn{sub x}Ga{sub 0.3}){sub 0.9}Sb{sub 0.1}](S{sub 0.15}Te{sub 0.2}Se{sub 1.65}) or Sn-x-CIGSe. Morphology, structure, and electrical property of Sn-doped CIGSe bulks were investigated. The composition of Sn-doped CIGSe is purposely designed for studying the doping effect on the CIGSe performance. The unexpected increase in hole concentration of CIGSe due to the donor doping is rationalized. A controllable n-type semiconductor is deliberately achieved for Sn-0.15-CIGSe and important for making a p/n homojunction in CIGSe solar cells. - Graphical abstract: The controls in defect type and electrical properties of Cu(In,Ga)Se{sub 2} by doping Sn{sup 4+} on the In{sup 3+} site. Highlights: • n-type Sn-CIGSe with n{sub e} of 6.4×10{sup 16} cm{sup ?3} and ?{sub e} of 2.3 cm{sup 2}/V s was obtained. • This n-type Sn-CIGSe was obtained by material design and composition control. • The reported n-type CIGSe was obtained from the Zn/CIGSe and CdS/CIGSe bilayers. • Extrinsic donor doping was explored through the results of electrical properties. • A n/p homojunction with Sn-CIGSe and undoped one can be used for solar cell devices.

Monsefi, Mehrdad; Kuo, Dong-Hau, E-mail: dhkuo@mail.ntust.edu.tw

2013-08-15T23:59:59.000Z

115

Desktop 3D printing of controlled release pharmaceutical bilayer tablets  

Science Journals Connector (OSTI)

Abstract Three dimensional (3D) printing was used as a novel medicine formulation technique for production of viable tablets capable of satisfying regulatory tests and matching the release of standard commercial tablets. Hydroxypropyl methylcellulose (HPMC 2208) (Methocel™ K100M Premium) and poly(acrylic acid) (PAA) (Carbopol® 974P NF) were used as a hydrophilic matrix for a sustained release (SR) layer. Hypromellose® (HPMC 2910) was used as a binder while microcrystalline cellulose (MCC) (Pharmacel® 102) and sodium starch glycolate (SSG) (Primojel®) were used as disintegrants for an immediate release (IR) layer. Commercial guaifenesin bi-layer tablets (GBT) were used as a model drug (Mucinex®) for this study. There was a favourable comparison of release of the active guaifenesin from the printed hydrophilic matrix compared with the commercially available GBT. The printed formulations were also evaluated for physical and mechanical properties such as weight variation, friability, hardness and thickness as a comparison to the commercial tablet and were within acceptable range as defined by the international standards stated in the United States Pharmacopoeia (USP). All formulations (standard tablets and 3D printed tablets) showed Korsmeyer-Peppas n values between 0.27 and 0.44 which indicates Fickian diffusion drug release through a hydrated HPMC gel layer.

Shaban A. Khaled; Jonathan C. Burley; Morgan R. Alexander; Clive J. Roberts

2014-01-01T23:59:59.000Z

116

Optical Properties and Potential Applications of Doped Semiconductor...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Optical Properties and Potential Applications of Doped Semiconductor Nanoparticles. Optical Properties and Potential Applications of Doped Semiconductor Nanoparticles. Abstract:...

117

Nanoporous microbead supported bilayers: stability, physical characterization, and incorporation of functional transmembrane proteins.  

SciTech Connect (OSTI)

The introduction of functional transmembrane proteins into supported bilayer-based biomimetic systems presents a significant challenge for biophysics. Among the various methods for producing supported bilayers, liposomal fusion offers a versatile method for the introduction of membrane proteins into supported bilayers on a variety of substrates. In this study, the properties of protein containing unilamellar phosphocholine lipid bilayers on nanoporous silica microspheres are investigated. The effects of the silica substrate, pore structure, and the substrate curvature on the stability of the membrane and the functionality of the membrane protein are determined. Supported bilayers on porous silica microspheres show a significant increase in surface area on surfaces with structures in excess of 10 nm as well as an overall decrease in stability resulting from increasing pore size and curvature. Comparison of the liposomal and detergent-mediated introduction of purified bacteriorhodopsin (bR) and the human type 3 serotonin receptor (5HT3R) are investigated focusing on the resulting protein function, diffusion, orientation, and incorporation efficiency. In both cases, functional proteins are observed; however, the reconstitution efficiency and orientation selectivity are significantly enhanced through detergent-mediated protein reconstitution. The results of these experiments provide a basis for bulk ionic and fluorescent dye-based compartmentalization assays as well as single-molecule optical and single-channel electrochemical interrogation of transmembrane proteins in a biomimetic platform.

Davis, Ryan W. (University of New Mexico, Albuquerque, NM); Brozik, James A. (University of New Mexico, Albuquerque, NM); Brozik, Susan Marie; Cox, Jason M. (University of New Mexico, Albuquerque, NM); Lopez, Gabriel P. (University of New Mexico, Albuquerque, NM); Barrick, Todd A. (University of New Mexico, Albuquerque, NM); Flores, Adrean (University of New Mexico, Albuquerque, NM)

2007-03-01T23:59:59.000Z

118

Bilayer self-assembly on a hydrophilic, deterministically nano-patterned surface  

SciTech Connect (OSTI)

We present measurements of the in-situ, microscopic architecture of a self-assembled bilayer at the interface between a regularly nano-patterned surface and an aqueous sub-phase using neutron reflectometry. The substrate is patterned with a rectangular array of nano-scaled holes. Because of the high quality of the pattern, using neutron reflectometry, we are able to map the surface-normal density distribution of the patterned silicon, the penetration of water into the pattern, and the distribution of a deposited film inside and outside of the etched holes. In this study, 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) single bilayers were deposited on the hydrophilic patterned surface. For bilayers deposited either by vesicle fusion (VF) or by the Langmuir Schaefer (L-S) technique, the most consistent model found to fit the data shows that the lipids form bilayer coatings on top of the substrate as well as the bottoms of the holes in an essentially conformal fashion. However, while there is a single bilayer on the unetched silicon surface, the lipids coating the bottoms of the holes form a complex bimodal structure consistent with a rough surface produced by the etching process. This study provides insight into film transfer both outside and inside regular nano-patterned features.

Smith, Gregory Scott [ORNL] [ORNL; Jung, Seung-Yong [ORNL] [ORNL; Browning, Jim [ORNL] [ORNL; Keum, Jong Kahk [ORNL] [ORNL; Lavrik, Nickolay V [ORNL] [ORNL; Alemseghed, Mussie G [ORNL] [ORNL; Collier, Pat [ORNL] [ORNL

2013-01-01T23:59:59.000Z

119

Anisotropic Motion and Molecular Dynamics of Cholesterol, Lanosterol, and Ergosterol in Lecithin Bilayers Studied by Quasi-elastic Neutron Scattering  

E-Print Network [OSTI]

Bilayers Studied by Quasi-elastic Neutron Scattering Emil Endress, Helmut Heller,§ He´le`ne CasaltaVised Manuscript ReceiVed June 27, 2002 ABSTRACT: Quasi-elastic neutron scattering (QENS) was employed to study of motion within the bilayer on the molecular dynamics time scale. In a recent quasi-elastic neutron

Brown, Michael F.

120

Comparing Simulations of Lipid Bilayers to Scattering Data: The GROMOS 43A1-S3 Force Field  

E-Print Network [OSTI]

, and excellent, fit to neutron scattering data occurs at an interpolated AN = 66.6 Ã?2 and the best lipid bilayers. It was not, however, compared to neutron scattering data which has become particularlyComparing Simulations of Lipid Bilayers to Scattering Data: The GROMOS 43A1-S3 Force Field Anthony

Nagle, John F.

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

PHYSICAL REVIEW B 85, 205443 (2012) Growth structure and work function of bilayer graphene on Pd(111)  

E-Print Network [OSTI]

PHYSICAL REVIEW B 85, 205443 (2012) Growth structure and work function of bilayer graphene on Pd of bilayer graphene on Pd(111). Low-energy electron diffraction analysis established that the two graphene layer. We propose that the faceted shapes are due to the zigzag-terminated edges bounding graphene

Ciobanu, Cristian

122

BI-LAYER p-n JUNCTION INTERCONNECTIONS FOR COAL BASED SOLID OXIDE FUEL CELLS  

SciTech Connect (OSTI)

In this report, a new approach for lower operating temperature solid oxide fuel cells (SOFCs) interconnections (IC) consisting of a bi-layer structure is proposed and analyzed. The bi-layer structure consists of a p-type layer exposed to cathodic gas (air/oxygen) and an n-type layer exposed to anodic gas (fuel). It is theoretically shown that the interfacial oxygen partial pressure which is an important design variable, is dependent primarily on the oxygen partial pressure gradient across the IC, the low level oxygen conductivities of the two layers and is largely independent of their electronic conductivities and the total current density through the IC material. Experimental difficulties in fabricating bi-layer structures are presently being addressed.

Srikanth Gopalan

2005-01-29T23:59:59.000Z

123

Proximity effect bilayer nano superconducting quantum interference devices for millikelvin magnetometry  

SciTech Connect (OSTI)

Superconducting quantum interference devices (SQUIDs) incorporating thin film nanobridges as weak links have sensitivities approaching that required for single spin detection at 4.2?K. However, due to thermal hysteresis they are difficult to operate at much lower temperatures which hinder their application to many quantum measurements. To overcome this, we have developed nanoscale SQUIDs made from titanium-gold proximity bilayers. We show that their electrical properties are consistent with a theoretical model developed for heat flow in bilayers and demonstrate that they enable magnetic measurements to be made on a sample at system temperatures down to 60 mK.

Blois, A., E-mail: a.blois@ucl.ac.uk; Rozhko, S.; Romans, E. J. [London Centre for Nanotechnology, University College London (UCL), 17-19 Gordon Street, London WC1H 0AH (United Kingdom); Hao, L.; Gallop, J. C. [National Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW (United Kingdom)

2013-12-21T23:59:59.000Z

124

Nonlinear interaction of two trapped-mode resonances in a bilayer "fish-scale" metamaterial  

E-Print Network [OSTI]

We report on a bistable light transmission through a bilayer "fish-scale" (meander-line) metamaterial. It is demonstrated that an all-optical switching may be achieved nearly the frequency of the high-quality-factor Fano-shaped trapped-mode resonance excitation. The nonlinear interaction of two closely spaced trapped-mode resonances in the bilayer structure composed with a Kerr-type nonlinear dielectric slab is analyzed in both frequency and time domains. It is demonstrated that these two resonances react differently on the applied intense light which leads to destination of a multistable transmission.

Tuz, Vladimir R; Mladyonov, Pavel L; Prosvirnin, Sergey L; Novitsky, Andrey V

2014-01-01T23:59:59.000Z

125

Doping of G Molecular Layer D  

E-Print Network [OSTI]

- Sn MCCs (Na4Sn2S6) GaAs substrate Doping Profile of a S-Sn doped (100) GaAs wafer g S-Sn doped Ga Based on three steps: Band Diagram of GaAs Based on three steps: I Reaction of dopant containing

Candea, George

126

Autocompensation in doped amorphous silicon  

Science Journals Connector (OSTI)

Studies based predominantly on luminescence and electron spin resonance provide strong evidence for defect formation concomitant with doping of glow discharge produced a?Si:H. In samples doped with boron or phosphorus the increase of non?radiative recombination observed in luminescence correlates with the increase of the dangling bond signal seen in light?induced ESR. This directly indicates an increase in the number of dangling?bond?like centers with doping. Compensation allows the Fermi level and dopant levels to be varied independently. In compensated samples with EF near midgap the number of dangling bond centers is reduced. An autocompensation mechanism is proposed to explain this Fermi level?dependent defect formation.

D. K. Biegelsen; R. A. Street; J. C. Knights

1981-01-01T23:59:59.000Z

127

Boron doping a semiconductor particle  

DOE Patents [OSTI]

A method (10,30) of boron doping a semiconductor particle using boric acid to obtain a p-type doped particle. Either silicon spheres or silicon powder is mixed with a diluted solution of boric acid having a predetermined concentration. The spheres are dried (16), with the boron film then being driven (18) into the sphere. A melt procedure mixes the driven boron uniformly throughout the sphere. In the case of silicon powder, the powder is metered out (38) into piles and melted/fused (40) with an optical furnace. Both processes obtain a p-type doped silicon sphere with desired resistivity. Boric acid is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirements.

Stevens, Gary Don (18912 Ravenglen Ct., Dallas, TX 75287); Reynolds, Jeffrey Scott (703 Horizon, Murphy, TX 75094); Brown, Louanne Kay (2530 Poplar Tr., Garland, TX 75042)

1998-06-09T23:59:59.000Z

128

Investigation of the effect of bilayer membrane structures and fluctuation amplitudes on SANS/SAXS profile for short membrane wavelength  

SciTech Connect (OSTI)

The effect of bilayer membrane structures and fluctuation amplitudes on small angle neutron scattering (SANS) and small angle X-ray scattering (SAXS) profile is investigated based on harmonic motions of the surfactant bilayers with bending as well as thickness fluctuation motions. In this study we consider the case in which the wavelength of the bilayer membrane is shorter than the thickness of the membrane. We find that the thickness of the surfactant bilayer membrane, d{sub m}, affects both q{sub dip} and q{sub peak} of I(q,0) profile, and that the fluctuation amplitude, a, of the membrane changes the peak of I(q,0). A simple formula is derived to estimate the thickness of the bilayer based on the q{sub dip} of the profile obtained from the simulation. The resulting estimates of the thickness of the bilayer with harmonic motion showed accuracy within 1%. Moreover, the bilayer thicknesses estimated from the proposed formula show an excellent agreement with the SANS and SAXS experimental results available in the literatures. We also propose a curve fit model, which describes the relationship between the fluctuation amplitude and the normalized q{sub peak} ratio. The present results show the feasibility of the simple formula to estimate the fluctuation amplitude based on the SANS and SAXS profiles.

Lee, Victor; Hawa, Takumi [School of Aerospace and Mechanical Engineering, The University of Oklahoma, Norman, Oklahoma 73019 (United States)] [School of Aerospace and Mechanical Engineering, The University of Oklahoma, Norman, Oklahoma 73019 (United States)

2013-09-28T23:59:59.000Z

129

Magnetization reversal and exchange bias effects in hard/soft ferromagnetic bilayers with orthogonal anisotropies  

E-Print Network [OSTI]

The magnetization reversal processes are discussed for exchange-coupled ferromagnetic hard/soft bilayers made from Co[subscript 0.66]Cr[subscript 0.22]Pt[subscript 0.12] (10 and 20 nm)/Ni (from 0 to 40 nm) films with ...

Ross, Caroline A.

130

Evidence for spontaneous interlayer phase coherence in a bilayer quantum Hall exciton condensate  

E-Print Network [OSTI]

double layer 2D electron gas sample. There are several equivalent ways to view the strongly correlatedEvidence for spontaneous interlayer phase coherence in a bilayer quantum Hall exciton condensate J of the excitonic Bose condensate which describes this remarkable quantum Hall state. q 2003 Published by Elsevier

Eisenstein, Jim

131

A Versatile Approach to the Generation of Fluid Supported Lipid Bilayers and Its Applications  

E-Print Network [OSTI]

of transport processes like the conduction of ion channels, the transport of substrate through transmembrane-coating of membrane lipids. Subsequen- tially, transmembrane proteins are incorporated by the fusion of transmembrane proteins in a bilayer and the visualization of the fusion of individual, membrane

132

Enhancement of the Morphology and Open Circuit Voltage in Bilayer Polymer/Fullerene Solar Cells  

Science Journals Connector (OSTI)

We describe the influence of thermal annealing on the performance of polymer bilayer solar cell devices of regioregular poly(3-hexylthiophene), regiorandom poly(3-hexylthiophene), or poly(3-hexyl-2,5-thienylene vinylene) (P3HTV), with C60 as the electron ...

Derek M. Stevens; Yang Qin; Marc A. Hillmyer; C. Daniel Frisbie

2009-06-09T23:59:59.000Z

133

NEUTRON SCATTERING SHOWS THAT CYTOCHROME b5 PENETRATES DEEPLY INTO THE LIPID BILAYER  

E-Print Network [OSTI]

NEUTRON SCATTERING SHOWS THAT CYTOCHROME b5 PENETRATES DEEPLY INTO THE LIPID BILAYER E. P. GOGOL to lipid vesicles using neutron small-angle scattering methods. To increase scat- tering contrast between of a highly deuterated phospholipid. Small-angle neutron diffraction patterns were collected in a series of H

134

SUPPLEMENTARY MATERIAL Lipid bilayer structure determined by the simultaneous analysis of neutron  

E-Print Network [OSTI]

scattering intensities I(q) for both neutrons and x-rays using )()()()( qPqPqIqF TSLC= , (1.) where PLC in structure between oriented and spherical bilayers experimentally using both neutron and x-ray scattering in (2). Our study concluded no difference between the two for x-ray and neutron scattering data

Nagle, John F.

135

Raman spectra of out-of-plane phonons in bilayer graphene  

E-Print Network [OSTI]

The double resonance Raman spectra of the overtone of the out-of-plane tangential optical (oTO) phonon and of combinations of the LO, ZO, and ZA phonons with one another are calculated for bilayer graphene. In the case of ...

Sato, Kentaro

136

Direct Visualization of Vesicle-Bilayer Complexes by Atomic Force Microscopy  

E-Print Network [OSTI]

vesicles and bilayers play a central role in cell physiology, enabling secretion, signaling, less is known about the structure and organization of lipids during this process. In addition, the interaction between lipids and proteins is known to be important for fusion. Evidence for this comes from

Kumar, Sanjay

137

Polymer-Cushioned Bilayers. I. A Structural Study of Various Preparation Methods Using Neutron Reflectometry  

E-Print Network [OSTI]

ABSTRACT This neutron reflectometry study evaluates the structures resulting from different methodsPolymer-Cushioned Bilayers. I. A Structural Study of Various Preparation Methods Using Neutron Reflectometry J. Y. Wong,* J. Majewski,# M. Seitz,* C. K. Park,* J. N. Israelachvili,* and G. S. Smith

Wong, Joyce

138

Metal-doped organic foam  

DOE Patents [OSTI]

Organic foams having a low density and very small cell size and method for producing same in either a metal-loaded or unloaded (nonmetal loaded) form are described. Metal-doped foams are produced by soaking a polymer gel in an aqueous solution of desired metal salt, soaking the gel successively in a solvent series of decreasing polarity to remove water from the gel and replace it with a solvent of lower polarity with each successive solvent in the series being miscible with the solvents on each side and being saturated with the desired metal salt, and removing the last of the solvents from the gel to produce the desired metal-doped foam having desired density cell size, and metal loading. The unloaded or metal-doped foams can be utilized in a variety of applications requiring low density, small cell size foam. For example, rubidium-doped foam made in accordance with the invention has utility in special applications, such as in x-ray lasers.

Rinde, James A. (Livermore, CA)

1982-01-01T23:59:59.000Z

139

Potential commercial application of a bi-layer bone-ligament regeneration scaffold to anterior cruciate ligament replacement  

E-Print Network [OSTI]

A business model was created in order to explore the commercial application of a bi-layer bone-ligament scaffold to the treatment of torn anterior cruciate ligaments (ACL) requiring replacement. The two main keys in producing ...

Li, Jessica C. (Jessica Ching-Yi)

2006-01-01T23:59:59.000Z

140

Feasibility of study magnetic proximity effects in bilayer “superconductor/ferromagnet” using waveguide-enhanced polarized neutron reflectometry  

Science Journals Connector (OSTI)

A resonant enhancement of the neutron standing waves is proposed to use in order to increase the magnetic neutron scattering from a “superconductor/ferromagnet” (S/F) bilayer. The model calculations show that ...

Yu. N. Khaydukov; Yu. V. Nikitenko; L. Bottyan; A. Rühm…

2010-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

ccsd-00000448(version1):26Jun2003 Swelling of phospholipid floating bilayers: the effect of chain length  

E-Print Network [OSTI]

: Fluctuations 61.12.Ha: Neutron reflectometry 68.15.+e: Liquid thin films I. INTRODUCTION The basic building.m.s. positions of the floating bilayer were determined by means of neutron specular reflectivity. Samples were

Paris-Sud XI, Université de

142

Synthesis and characterization of P-doped amorphous and nanocrystallin...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

characterization of P-doped amorphous and nanocrystalline Si. Synthesis and characterization of P-doped amorphous and nanocrystalline Si. Abstract: P-doped amorphous Si (a-Si) was...

143

Doping Graphene with Metal Contacts  

Science Journals Connector (OSTI)

Making devices with graphene necessarily involves making contacts with metals. We use density functional theory to study how graphene is doped by adsorption on metal substrates and find that weak bonding on Al, Ag, Cu, Au, and Pt, while preserving its unique electronic structure, can still shift the Fermi level with respect to the conical point by ?0.5??eV. At equilibrium separations, the crossover from p-type to n-type doping occurs for a metal work function of ?5.4??eV, a value much larger than the graphene work function of 4.5 eV. The numerical results for the Fermi level shift in graphene are described very well by a simple analytical model which characterizes the metal solely in terms of its work function, greatly extending their applicability.

G. Giovannetti; P. A. Khomyakov; G. Brocks; V. M. Karpan; J. van den Brink; P. J. Kelly

2008-07-10T23:59:59.000Z

144

Acid Doped Membranes for High Temperature PEMFC  

Broader source: Energy.gov [DOE]

Presentation on Acid Doped Membranes for High Temperature PEMFC to the High Temperature Membrane Working Group, May 25, 2004 in Philadelphia, PA.

145

Lanthanide doped strontium barium mixed halide scintillators  

DOE Patents [OSTI]

The present invention provides for a composition comprising an inorganic scintillator comprising a lanthanide-doped strontium barium mixed halide useful for detecting nuclear material.

Gundiah, Gautam; Bizarri, Gregory; Hanrahan, Stephen M; Bourret-Courchesne, Edith; Derenzo, Stephen E

2013-07-16T23:59:59.000Z

146

Lanthanide doped barium phosphorous oxide scintillators  

DOE Patents [OSTI]

The present invention provides for a composition comprising an inorganic scintillator comprising a lanthanide-doped barium phosphorous oxide useful for detecting nuclear material.

Borade, Ramesh B; Bourret-Courchesne, Edith; Denzo, Stephen E

2013-02-26T23:59:59.000Z

147

Chromium(III)-doped pillared clays (PILC's)  

Science Journals Connector (OSTI)

Chromium(III)-doped pillared clays (PILC's) ... First, calcined Al-PILC was dispersed into an aqueous solution of sodium or ammonium ions. ...

K. A. Carrado; S. L. Suib; N. D. Skoularikis; R. W. Coughlin

1986-11-01T23:59:59.000Z

148

Doping of Glass with Lithium Ion  

Science Journals Connector (OSTI)

Our discovery that the Li+ uptake by the glass walls of the vessels used in the experiments can be used for doping purposes was purely surreptitious. ...

Greg Moakes; Lawrence A. Bottomley; Jiri Janata

2005-01-12T23:59:59.000Z

149

Watermelon-like iron nanoparticles: Cr doping effect on magnetism...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Watermelon-like iron nanoparticles: Cr doping effect on magnetism and magnetization interaction reversal. Watermelon-like iron nanoparticles: Cr doping effect on magnetism and...

150

Thickness Dependency of Thin Film Samaria Doped Ceria for Oxygen...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Dependency of Thin Film Samaria Doped Ceria for Oxygen Sensing . Thickness Dependency of Thin Film Samaria Doped Ceria for Oxygen Sensing . Abstract: High temperature oxygen...

151

Organic photovoltaic devices with the bilayer cathode interfacial structure of pyromellitic dianhydride and lithium fluoride  

Science Journals Connector (OSTI)

In this study, we fabricated and characterized an organic photovoltaic (OPV) device with a pyromellitic dianhydride (PMDA)/lithium fluoride (LiF) cathode interfacial layer between poly(3-hexylthiophene?2,5-diyl)(P3HT)+[6,6]-phenyl C61 butyric acid methyl ester (PCBM) and Al. Compared to the OPV device with a LiF-only cathode interfacial layer having a power conversion efficiency (PCE) of 2.7%, the OPV device with the bilayer cathode interfacial structure [PMDA (0.3 nm)/LiF (0.7 nm)] exhibited a reduced resistance and a PCE value enhanced to 3.9% under an illumination condition of 100 mW cm?2 (AM1.5). The observed improvement of the OPV characteristics was attributed to the reduced leakage current of the device by the bilayer cathode interfacial layer.

Eunkyoung Nam; Seungsik Oh; Donggeun Jung; Hyoungsub Kim; Heeyeop Chae; Junsin Yi

2012-01-01T23:59:59.000Z

152

Excitonic Effects on the Optical Response of Graphene and Bilayer Graphene  

Science Journals Connector (OSTI)

We present first-principles calculations of many-electron effects on the optical response of graphene, bilayer graphene, and graphite employing the GW-Bethe Salpeter equation approach. We find that resonant excitons are formed in these two-dimensional semimetals. The resonant excitons give rise to a prominent peak in the absorption spectrum near 4.5 eV with a different line shape and significantly redshifted peak position from those of an absorption peak arising from interband transitions in an independent quasiparticle picture. In the infrared regime, our calculated optical absorbance per graphene layer is approximately a constant, 2.4%, in agreement with recent experiments; additional low frequency features are found for bilayer graphene because of band structure effects.

Li Yang; Jack Deslippe; Cheol-Hwan Park; Marvin L. Cohen; Steven G. Louie

2009-10-28T23:59:59.000Z

153

Brillouin light scattering study of spin waves in NiFe/Co exchange spring bilayer films  

SciTech Connect (OSTI)

Spin waves are investigated in Permalloy(Ni{sub 80}Fe{sub 20})/Cobalt(Co) exchange spring bilayer thin films using Brillouin light scattering (BLS) experiment. The magnetic hysteresis loops measured by magneto-optical Kerr effect show a monotonic decrease in coercivity of the bilayer films with increasing Py thickness. BLS study shows two distinct modes, which are modelled as Damon-Eshbach and perpendicular standing wave modes. Linewidths of the frequency peaks are found to increase significantly with decreasing Py layer thickness. Interfacial roughness causes to fluctuate exchange coupling at the nanoscale regimes and the effect is stronger for thinner Py films. A quantitative analysis of the magnon linewidths shows the presence of strong local exchange coupling field which is much larger compared to macroscopic exchange field.

Haldar, Arabinda; Banerjee, Chandrima; Laha, Pinaki; Barman, Anjan, E-mail: abarman@bose.res.in [Thematic Unit of Excellence on Nanodevice Technology, Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata 700098 (India)

2014-04-07T23:59:59.000Z

154

Electron dynamics of the buffer layer and bilayer graphene on SiC  

SciTech Connect (OSTI)

Angle- and time-resolved two-photon photoemission (TPPE) was used to investigate electronic states in the buffer layer of 4H-SiC(0001). An image potential state (IPS) series was observed on this strongly surface-bound buffer layer, and dispersion measurements indicated free-electron-like behavior for all states in this series. These results were compared with TPPE taken on bilayer graphene, which also show the existence of a free-electron-like IPS series. Lifetimes for the n?=?2, and n?=?3 states were obtained from time-resolved TPPE; slightly increased lifetimes were observed in the bilayer graphene sample for the n?=?2 the n?=?3 states. Despite the large band gap of graphene at the center of the Brillouin zone, the lifetime results demonstrate that the graphene layers do not behave as a simple tunneling barrier, suggesting that the buffer layer and graphene overlayers play a direct role in the decay of IPS electrons.

Shearer, Alex J.; Caplins, Benjamin W.; Suich, David E.; Harris, Charles B., E-mail: cbharris@berkeley.edu [Department of Chemistry, University of California at Berkeley, Berkeley, California 94720 (United States); Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Johns, James E. [Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455 (United States); Hersam, Mark C. [Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Department of Chemistry, Northwestern University, Evanston, Illinois 60208 (United States)

2014-06-09T23:59:59.000Z

155

Biaxially aligned buffer layers of cerium oxide, yttria stabilized zirconia, and their bilayers  

SciTech Connect (OSTI)

Biaxially aligned cerium oxide (CeO{sub 2}) and yttria stabilized zirconia (YSZ) films were deposited on Ni-based metal (Hastelloy C276) substrates held at room temperature using ion beam assisted (IBAD) magnetron deposition with the ion beam directed at 55{degree} to the normal of the film plane. In addition, we achieved, room-temperature epitaxial growth of CeO{sub 2} by bias sputtering to form biaxially aligned CeO{sub 2}/YSZ bilayers. The crystalline structure and in-plane orientation of films was investigated by x-ray diffraction techniques. Both the IBAD CeO{sub 2} and YSZ films, and the CeO{sub 2}/YSZ bilayers have a (111) pole in the ion beam direction. {copyright} {ital 1997 American Institute of Physics.}

Gnanarajan, S.; Katsaros, A.; Savvides, N. [CSIRO Telecommunications and Industrial Physics, Lindfield NSW 2070 (Australia)] [CSIRO Telecommunications and Industrial Physics, Lindfield NSW 2070 (Australia)

1997-05-01T23:59:59.000Z

156

Bilayer-Spanning DNA Nanopores with Voltage-Switching between Open and Closed State  

E-Print Network [OSTI]

smaller PEGs are assumed to enter the pore. PEG sizing also clarifies that the main ion conducting path runs through the membrane-spanning channel lumen as opposed to any proposed gap between the outer pore wall and the lipid bilayer. At higher voltages... for the development of new DNA nanopores for nanobiotechnology. Building rationally designed nanoscale porous structures that mediate transport across membranes is of general interest in fundamental and applied science.1, 2 Biomimetic engineered nanopores3...

Seifert, Astrid; Göpfrich, Kerstin; Burns, Jonathan R.; Fertig, Niels; Keyser, Ulrich F.; Howorka, Stefan

2014-10-22T23:59:59.000Z

157

Interplay between intrinsic and stacking-fault magnetic domains in bi-layered manganites  

SciTech Connect (OSTI)

We present a low temperature X-ray photoemission electron microscopy study of the bi-layered manganite compound La{sub 1.2}Sr{sub 1.8}Mn{sub 2}O{sub 7} (BL-LSMO) to investigate the influence of stacking faults, which are structurally and magnetically different from the bi-layered host. In BL-LSMO small magnetic moment persists to T* = 300K, well above the Curie temperature of 120K (T{sub C}). Our magnetic images show that 3D stacking faults are responsible for the T* transition. Furthermore, close to the T{sub C}, stacking faults are well coupled to the bi-layered host with latter magnetic domains controlling the spin direction of the stacking faults. Contrary to recent reports, we find that stacking faults do not seed magnetic domains in the host via an exchange spring mechanism and the intrinsic T{sub C} of the BL-LSMO is not lower than 120K.

Hossain, M.A; Burkhardt, Mark H.; Sarkar, S.; Ohldag, H.; Chuang, Y.-D.; Scholl, A.; Young, A.T.; Doran, A.; Dessau, D.S.; Zheng, H.; Mitchell, J.F.; Durr, H.A.; Stohr, J.

2012-09-11T23:59:59.000Z

158

Phase diagram of the CF{sub 4} monolayer and bilayer on graphite  

SciTech Connect (OSTI)

We report an experimental study of physisorbed monolayers and bilayers of CF{sub 4} on graphite using infrared reflection absorption spectroscopy supplemented by ellipsometry. The symmetric C–F stretch mode ?{sub 3} near 1283 cm{sup ?1} in the gas is strongly blue shifted in the film by dynamic dipole coupling. This blue shift provides a very sensitive measure of the inter-molecular spacing in the monolayer and, less directly, in the bilayer. We find that important corrections are necessary to the volumetric coverage scales used in previous heat capacity and x-ray diffraction studies of this system. This requires quantitative and some qualitative changes to the previously proposed phase diagram. We find evidence for a new phase transition in the middle of the hexagonal incommensurate region and construct new phase diagrams in both the variables coverage-temperature and chemical potential-temperature. We determine the compressibility and thermal expansion in the low-pressure hexagonal incommensurate phase and values for the entropy change in several phase transitions. Below about 55 K there is evidence of solution of up to 7% of an impurity, most likely CO, in our monolayer but not the bilayer film.

Thomas, Petros; Hess, George B., E-mail: gbh@virginia.edu [Physics Department, University of Virginia, Charlottesville, Virginia 22904 (United States)

2014-05-21T23:59:59.000Z

159

Doped Carbon Nanotubes for Hydrogen Storage  

E-Print Network [OSTI]

Doped Carbon Nanotubes for Hydrogen Storage U. S. DOE Hydrogen Program Annual Review May, 2003 structure carbon nanotube systems ·Not restricted to physisorption or chemisorption (weak covalent bond structures of doped carbon nanotubes APPROACH Based on C-H bond Dihydrogen bond H H M = + charge = - charge

160

Accelerometer-Based method for extracting respiratory and cardiac gating information for dual gating during nuclear medicine imaging  

Science Journals Connector (OSTI)

Both respiratory and cardiac motions reduce the quality and consistency of medical imaging specifically in nuclear medicine imaging. Motion artifacts can be eliminated by gating the image acquisition based on the respiratory phase and cardiac contractions ...

Mojtaba Jafari Tadi, Tero Koivisto, Mikko Pänkäälä, Ari Paasio

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Doping-induced metal-insulator transition in aluminum-doped 4H silicon P. Achatz,1,2,a  

E-Print Network [OSTI]

Doping-induced metal-insulator transition in aluminum-doped 4H silicon carbide P. Achatz,1,2,a J an experimental determination of the doping-induced metal-insulator transition in aluminum-doped 4H silicon concentration lying between 6.4 and 8.7 1020 cm-3 for the metal-insulator transition in these epilayers grown

Paris-Sud XI, Université de

162

Doping of CdS nanoparticles  

Science Journals Connector (OSTI)

The doping of semiconductor nanoparticles is introduced and examined via doping of cadmium sulfide nanoparticles both by chemical bath deposition route with In3+ cations and by thermal annealing route with Cl? anions. The CdS nanoparticles (10–20 nm in size) were prepared by mixing CdCl2 and Na2S solutions stabilized with pyridine both in absence and in presence of InCl3 additives. The doping of the nanostructured CdS films prepared from CdS nanoparticles dispersions was performed by additives of aqueous CdCl2 solution followed by the film annealing. Due to the used doping procedure the increase of the film conductivity began at temperature ?300 °C, which was far lower than temperature inducing the doping of polycrystalline CdS films and not yet enough for the noticeable recrystallization of CdS nanoparticles into larger domains. The In2S3 and CdCl2 doping of CdS nanoparticles resulted in changes in electronic absorption and luminescence spectra of the nanoparticle dispersions and films. The phenomenon of the easier doping of CdS nanoparticles is discussed in terms of the high surface energy of CdS nanoparticles.

N.M. Osipyonok; A.F. Singaevsky; Yu.V. Noskov; Yu.P. Piryatinski; P.S. Smertenko; O.P. Dimitriev; A.A. Pud

2008-01-01T23:59:59.000Z

163

CVD Growth of Mono-and Bi-Layer Graphene from Ethanol Xiao Chen, Pei Zhao, Bo Hou, Shohei Chiashi and Shigeo Maruyama  

E-Print Network [OSTI]

CVD Growth of Mono- and Bi-Layer Graphene from Ethanol Xiao Chen, Pei Zhao, Bo Hou, Shohei Chiashi understood. Here we report utilizing CVD to produce mono- and bi-layer graphene from ethanol. By using ethanol as carbon source, we carefully studied the CVD parameter for the growth process, and their effects

Maruyama, Shigeo

164

Effect of radical fluorination on mono- and bi-layer graphene in Ar/F{sub 2} plasma  

SciTech Connect (OSTI)

Fluorinated graphene has the possibility to achieve unique properties and functions in graphene. We propose a highly controlled fluorination method utilizing fluorine radicals in Ar/F{sub 2} plasma. To suppress ion bombardments and improve the reaction with fluorine radicals on graphene, the substrate was placed 'face down' in the plasma chamber. Although monolayer graphene was more reactive than bilayer, fluorination of bilayer reached the level of I{sub D}/I{sub G} {approx} 0.5 in Raman D peak intensity at 532 nm excitation. Annealing fluorinated samples proved reversibility of radical fluorination for both mono- and bi-layer graphenes. X-ray photoelectron spectroscopy showed the existence of carbon-fluorine bonding.

Tahara, K.; Iwasaki, T.; Hatano, M. [Department of Physical Electronics, Tokyo Institute of Technology, Tokyo 152-8552 (Japan); Matsutani, A. [Semiconductor and MEMS Processing Center, Technical Department, Tokyo Institute of Technology, Tokyo 226-8503 (Japan)

2012-10-15T23:59:59.000Z

165

PEN/Si3N4 bilayer film for dc bus capacitors in power converters in hybrid electric vehicles  

Science Journals Connector (OSTI)

High performance hybrid bilayer capacitorfilm has been developed by controlled deposition of silicon nitride (Si3N4) on polyethylene naphthalate (PEN). It was found that silicon nitride prepared with plasma-enhanced chemical vapor deposition can significantly increase the dielectric constant (K) and energy density of PEN by more than 20% and 50% respectively. Moreover the PEN/Si3N4 bilayer hybrid film also exhibits appropriate mechanical and thermal properties for capacitor winding. The high operating temperature and energy density of the PEN/Si3N4 bilayer dielectric film are very attractive for dc bus capacitors used in power inverters or converters found in hybrid electric vehicles wind turbine generators grid-tied photovoltaics and smart grid as well as pulsed power systems.

Chen Zou; Qiming Zhang; Shihai Zhang; Douglas Kushner; Xin Zhou; Richard Bernard; Raymond J. Orchard Jr.

2011-01-01T23:59:59.000Z

166

Deuterium absorption in Mg70Al30 thin films with bilayer catalysts: A comparative neutron reflectometry study  

Science Journals Connector (OSTI)

We present a neutron reflectometry study of deuterium absorption in thin films of Al-containing Mg alloys capped with a Ta/Pd, Ni/Pd and Ti/Pd-catalyst bilayer. The measurements were performed at room temperature over the 0–1 bar pressure range under quasi-equilibrium conditions. The modeling of the measurements provided a nanoscale representation of the deuterium profile in the layers at different stages of the absorption process. The absorption mechanism observed was found to involve spillover of atomic deuterium from the catalyst layer to the Mg alloy phase, followed by the deuteration of the Mg alloy. Complete deuteration of the Mg alloy occurs in a pressure range between 100 and 500 mbar, dependent on the type of bilayer catalyst. The use of a Ti/Pd bilayer catalyst yielded the best results in terms of both storage density and kinetic properties.

Eric Poirier; Chris T. Harrower; Peter Kalisvaart; Adam Bird; Anke Teichert; Dirk Wallacher; Nico Grimm; Roland Steitz; David Mitlin; Helmut Fritzsche

2011-01-01T23:59:59.000Z

167

Unconventional Air-Stable Interdigitated Bilayer Formed by 2,3-Disubstituted Fatty Acid Methyl Esters  

Science Journals Connector (OSTI)

The diffusion-limited aggregation (DLA) model is applied to describe the formation of the fractal structures of the bilayer as observed in the second plateau. ... For the fluorescence microscopy investigations, the film balance (144 cm2, Riegler & Kirstein) was mounted onto the stage of the Olympus microscope BX-FLA (Hamburg, Germany) equipped with a mercury lamp (USH-102D 100 W, power supply unit BH2-RFL-T3), an objective (LMPLFL 50×), and a CCD camera with a camera controller (Hamamatsu C4742-95, Hamamatsu, Japan). ...

Xiaodong Chen; Susanne Wiehle; Markus Weygand; Gerald Brezesinski; Ute Klenz; Hans-Joachim Galla; Harald Fuchs; Günter Haufe; Lifeng Chi

2005-10-05T23:59:59.000Z

168

Effect of Support Corrugation on Silica Xerogel?Supported Phase-Separated Lipid Bilayers  

Science Journals Connector (OSTI)

Furthermore, the lateral mobility of the lipids was confirmed for lipid bilayers supported by porous silica xerogel and aerogel surfaces. ... The fluorescence recovery images were captured with the excitation light that was attenuated at least 400 times (by the use of neutral density filters) to prevent further bleaching. ... The emission light was filtered by a 568 nm notch filter (Kaiser Optical Systems, Ann Arbor, MI) and a confocal pinhole (50 ?m diameter, Thorlabs, Newton, NJ) and then split by a 50/50 beam-splitter before finally being focused into two avalanche photo diodes (APD) (PerkinElmer). ...

Emel I. Goksu; Barbara A. Nellis; Wan-Chen Lin; Joe H. Satcher, Jr.; Jay T. Groves; Subhash H. Risbud; Marjorie L. Longo

2009-02-11T23:59:59.000Z

169

Gates controlled parallel-coupled double quantum dot on both single layer and bilayer graphene  

E-Print Network [OSTI]

Here we report the fabrication and quantum transport measurements of gates controlled parallel-coupled double quantum dot on both bilayer and single layer graphene. It is shown that the interdot coupling strength of the parallel double dots can be effectively tuned from weak to strong regime by both the in-plane plunger gates and back gate. All the relevant energy scales and parameters of the graphene parallel-coupled double dot can be extracted from the honeycomb charge stability diagrams revealed through the transport measurements.

Lin-Jun Wang; Guo-Ping Guo; Da Wei; Gang Cao; Tao Tu; Ming Xiao; Guang-Can Guo; A. M. Chang

2011-04-22T23:59:59.000Z

170

High transition temperature superconductor/insulator bilayers for the development of ultra-fast electronics  

SciTech Connect (OSTI)

High transition temperature superconductor (HTc)/SrTiO{sub 3} (STO) bilayers were fabricated by sputtering deposition on (100) STO substrates. Their transport and morphological properties were characterized using conductive atomic force microscopy. The STO barriers present good insulating properties, with long attenuation lengths (? ? 1 nm) which reduce the junction resistance and increase the operating critical current. The samples present roughness values smaller than 1 nm, with an extremely low density of surface defects (?5 × 10{sup ?5} defects/?m{sup 2}). The high control of the barrier quality over large defect free surfaces is encouraging for the development of microelectronics devices based in HTc Josephson junctions.

Sirena, M.; Félix, L. Avilés [Consejo Nacional de Investigaciones Científicas y Técnicas, Centro Atómico Bariloche, CNEA, Bustillo 9500, 8400 Bariloche (Argentina) [Consejo Nacional de Investigaciones Científicas y Técnicas, Centro Atómico Bariloche, CNEA, Bustillo 9500, 8400 Bariloche (Argentina); Instituto Balseiro, Universidad Nacional de Cuyo and CNEA, 8400 Bariloche (Argentina); Haberkorn, N. [Consejo Nacional de Investigaciones Científicas y Técnicas, Centro Atómico Bariloche, CNEA, Bustillo 9500, 8400 Bariloche (Argentina)] [Consejo Nacional de Investigaciones Científicas y Técnicas, Centro Atómico Bariloche, CNEA, Bustillo 9500, 8400 Bariloche (Argentina)

2013-07-29T23:59:59.000Z

171

Monte-Carlo study of the phase transition in the AA-stacked bilayer graphene  

E-Print Network [OSTI]

Tight-binding model of the AA-stacked bilayer graphene with screened electron-electron interactions has been studied using the Hybrid Monte Carlo simulations on the original double-layer hexagonal lattice. Instantaneous screened Coulomb potential is taken into account using Hubbard-Stratonovich transformation. G-type antiferromagnetic ordering has been studied and the phase transition with spontaneous generation of the mass gap has been observed. Dependence of the antiferromagnetic condensate on the on-site electron-electron interaction is examined.

Nikolaev, A A

2014-01-01T23:59:59.000Z

172

Monte-Carlo study of the phase transition in the AA-stacked bilayer graphene  

E-Print Network [OSTI]

Tight-binding model of the AA-stacked bilayer graphene with screened electron-electron interactions has been studied using the Hybrid Monte Carlo simulations on the original double-layer hexagonal lattice. Instantaneous screened Coulomb potential is taken into account using Hubbard-Stratonovich transformation. G-type antiferromagnetic ordering has been studied and the phase transition with spontaneous generation of the mass gap has been observed. Dependence of the antiferromagnetic condensate on the on-site electron-electron interaction is examined.

A. A. Nikolaev; M. V. Ulybyshev

2014-12-03T23:59:59.000Z

173

Dynamic selective switching in antiferromagnetically-coupled bilayers close to the spin reorientation transition  

E-Print Network [OSTI]

: http://scitation.aip.org/termsconditions. Downloaded to IP: 131.111.185.7 On: Thu, 09 Oct 2014 15:47:13 18Y. L. Iunin, Y. P. Kabanov, V. I. Nikitenko, X. M. Cheng, D. Clarke, O. A. Tretiakov, O. Tchernyshyov, A. J. Shapiro, R. D. Shull, and C. L. Chien... Dynamic selective switching in antiferromagnetically-coupled bilayers close to the spin reorientation transition A. Fernández-Pacheco, F. C. Ummelen, R. Mansell, D. Petit, J. H. Lee, H. J. M. Swagten, and R. P. Cowburn Citation: Applied Physics...

Fern ández-Pacheco, A.; Ummelen, F. C.; Mansell, R.; Petit, D.; Lee, J. H.; Swagten, H. J. M.; Cowburn, R. P.

2014-09-05T23:59:59.000Z

174

Spin-wave excitation and propagation in microstructured waveguides of yttrium iron garnet/Pt bilayers  

SciTech Connect (OSTI)

We present an experimental study of spin-wave excitation and propagation in microstructured waveguides consisting of a 100?nm thick yttrium iron garnet/platinum (Pt) bilayer. The life time of the spin waves is found to be more than an order of magnitude higher than in comparably sized metallic structures, despite the fact that the Pt capping enhances the Gilbert damping. Utilizing microfocus Brillouin light scattering spectroscopy, we reveal the spin-wave mode structure for different excitation frequencies. An exponential spin-wave amplitude decay length of 31??m is observed which is a significant step towards low damping, insulator based micro-magnonics.

Pirro, P.; Chumak, A. V.; Lägel, B.; Leven, B.; Hillebrands, B. [Fachbereich Physik and Landesforschungszentrum OPTIMAS, Technische Universität Kaiserslautern, D-67663 Kaiserslautern (Germany)] [Fachbereich Physik and Landesforschungszentrum OPTIMAS, Technische Universität Kaiserslautern, D-67663 Kaiserslautern (Germany); Brächer, T. [Fachbereich Physik and Landesforschungszentrum OPTIMAS, Technische Universität Kaiserslautern, D-67663 Kaiserslautern (Germany) [Fachbereich Physik and Landesforschungszentrum OPTIMAS, Technische Universität Kaiserslautern, D-67663 Kaiserslautern (Germany); Graduate School Materials Science in Mainz, Gottlieb-Daimler-Strasse 47, D-67663 Kaiserslautern (Germany); Dubs, C.; Surzhenko, O.; Görnert, P. [Innovent e.V., Prüssingstraße 27B, 07745 Jena (Germany)] [Innovent e.V., Prüssingstraße 27B, 07745 Jena (Germany)

2014-01-06T23:59:59.000Z

175

Influence of Disorder on Conductance in Bilayer Graphene under Perpendicular Electric Field  

Science Journals Connector (OSTI)

Steep increase of the resistance is observed under high electric field; however, the resistance does not diverge even at low temperatures. ... Here, from the elementary electrostatics, the electric field is given by E = {(Vtg ? Vtg0) ? (Vbg ? Vbg0)}/{(?0/?b)db + dgr + (?0/?t)dt}, where Vtg0 and Vbg0 are the gate voltages that give the minimum resistance on the diagonal ridge line, corresponding to E = 0, and dgr is the thickness of the bilayer graphene, which is negligible in the expression for our device structure. ...

Hisao Miyazaki; Kazuhito Tsukagoshi; Akinobu Kanda; Minoru Otani; Susumu Okada

2010-08-30T23:59:59.000Z

176

Materials - Transient doping success | ornl.gov  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Materials - Transient doping success . . . Materials - Transient doping success . . . Using a scanning tunneling microscope tip, scientists at the University of Rostock, Germany, and Oak Ridge National Laboratory have accomplished something thought to be virtually impossible. "We devised an approach to change electronic properties of one-dimensional systems without introducing dopant atoms that effectively cut the chain into smaller pieces," said Paul Snijders of ORNL's Materials Science and Technology Division. This discovery, known as transient doping and detailed in a paper published in Physical Review Letters, was accomplished using only electrons. That makes it especially intriguing to co-author Snijders and colleagues who note that the doping of materials, which changes the number of electrons, has led to

177

Controlled doping of graphene using ultraviolet irradiation  

SciTech Connect (OSTI)

The electronic properties of graphene are tunable via doping, making it attractive in low dimensional organic electronics. Common methods of doping graphene, however, adversely affect charge mobility and degrade device performance. We demonstrate a facile shadow mask technique of defining electrodes on graphene grown by chemical vapor deposition (CVD) thereby eliminating the use of detrimental chemicals needed in the corresponding lithographic process. Further, we report on the controlled, effective, and reversible doping of graphene via ultraviolet (UV) irradiation with minimal impact on charge mobility. The change in charge concentration saturates at {approx}2 Multiplication-Sign 10{sup 12} cm{sup -2} and the quantum yield is {approx}10{sup -5} e/photon upon initial UV exposure. This simple and controlled strategy opens the possibility of doping wafer-size CVD graphene for diverse applications.

Luo Zhengtang [Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong); Pinto, Nicholas J.; Davila, Yarely [Department of Physics and Electronics, University of Puerto Rico at Humacao, Humacao, 00792 (Puerto Rico); Charlie Johnson, A. T. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396 (United States)

2012-06-18T23:59:59.000Z

178

Performance test of Ti/Au bilayer TES microcalorimeter in combination with continuous ADR  

SciTech Connect (OSTI)

Performance test of a Ti/Au bilayer TES microcalorimeter has been made in combination with a continuous adiabatic demagnetization refrigerator (CADR). The CADR has four stages of ADR to produce continuous cooling by recycling them in dedicated order, and is cryogen-free utilizing a 4K-GM refrigerator. We installed a Ti/Au bilayer TES microcalorimeter and 420-series SQUID array to readout the X-ray signal on the 1st (coldest) stage of the CADR. We successfully operated the CADR at temperature of 120 mK in continuous mode more than 27 hr, however, FWHM energy resolution of the TES microcalorimeter was degraded to 45 eV at 6 keV, as compared to 10 eV when measured in a dilution refrigerator. This is mainly because the temperature stability was not good enough (about 0.6 mK) and the operation temperature was not sufficiently lower than the transition temperature T{sub c} = 135mK of the TES. We operated the TES microcalorimeter at the operation temperature of 105 mK in one-shot mode and the resolution was improved to 30 eV. We also found that the operating point of the TES was affected by the magnetic field of the 3rd and 4th ADR recycle. More complete shielding of the magnetic field is essential for further improvement of the performance of the TES microcalorimeter.

Ishisaki, Y.; Akamatsu, H.; Hoshino, A. [Department of Physics, Tokyo Metropolitan University 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397 (Japan); Numazawa, T.; Kamiya, K. [Tsukuba Magnet Laboratory, NIMS, 3-13 Sakura, Tsukuba 305-0003 (Japan); Fujimoto, R.; Kojima, Y. [Faculty of Mathematics and Physics, Kanazawa University, Kakuma, Kanazawa, Ishikawa 920-1192 (Japan); Shinozaki, K. [Aerospace Research and Development Directorate, JAXA, 1-1 Sengen, Tsukuba, Ibaraki 305-8505 (Japan); Institute of Space and Astronautical Science, JAXA, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan); Mitsuda, K. [Institute of Space and Astronautical Science, JAXA, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan); Shirron, P. [NASA/Goddard Space Flight Center (GSFC), Greenbelt, MD 20771 (United States)

2009-12-16T23:59:59.000Z

179

Electric-field-induced plasmon in AA-stacked bilayer graphene  

SciTech Connect (OSTI)

The collective excitations in AA-stacked bilayer graphene for a perpendicular electric field are investigated analytically within the tight-binding model and the random-phase approximation. Such a field destroys the uniform probability distribution of the four sublattices. This drives a symmetry breaking between the intralayer and interlayer polarization intensities from the intrapair band excitations. A field-induced acoustic plasmon thus emerges in addition to the strongly field-tunable intrinsic acoustic and optical plasmons. At long wavelengths, the three modes show different dispersions and field dependence. The definite physical mechanism of the electrically inducible and tunable mode can be expected to also be present in other AA-stacked few-layer graphenes. -- Highlights: •The analytical derivations are performed by the tight-binding model. •An electric field drives the non-uniformity of the charge distribution. •A symmetry breaking between the intralayer and interlayer polarizations is illustrated. •An extra plasmon emerges besides two intrinsic modes in AA-stacked bilayer graphene. •The mechanism of a field-induced mode is present in AA-stacked few-layer graphenes.

Chuang, Y.C., E-mail: yingchih.chuang@gmail.com; Wu, J.Y., E-mail: yarst5@gmail.com; Lin, M.F., E-mail: mflin@mail.ncku.edu.tw

2013-12-15T23:59:59.000Z

180

TOF-SIMS/MALDI-TOF combination for the molecular weight depth profiling of polymeric bilayer  

Science Journals Connector (OSTI)

Abstract A polymeric bilayer composed of two poly(styrene) layers differing by their molecular weights (MW) was elaborated to mimic a MW gradient and analyzed by a combination of TOF-SIMS, MALDI-MS and Nanoscratch (NS). A direct TOF-SIMS profiling conducted using a Cs+ ion beam lead to the detection of fragments from carbonated layers without any data about their MW, making the fine bilayer architecture indistinguishable. Spots of various depths were hence created using the same Cs+ ion bombardment for different sputtering times, and further mass-analyzed by the recently developed Surface-Layer MALDI-MS technique, to evaluate the MW of the very top polymeric layer of each crater. The off-line combination of ion etching and LASER analysis allowed a molecular weight depth profile to be plotted, as a function of the physical depth measured by NS in each crater (instead of the usual sputter time). This original coupling is expected to provide useful molecular and/or molecular weight data about complex organic and/or polymeric multi-layers or gradients.

Thierry Fouquet; Grégory Mertz; Nicolas Desbenoit; Gilles Frache; David Ruch

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


181

cholesterol in phosphatidylcholine bilayers Assess the nature of cholesterol-lipid interactions through the chemical potential of  

E-Print Network [OSTI]

cholesterol in phosphatidylcholine bilayers Assess the nature of cholesterol-lipid interactions, see: Reprints www.pnas.org/misc/reprints.shtml To order reprints, see: Notes: #12;Assess the nature a vital role in determining the physiochemical properties of cell membranes. However, the detailed nature

Huang, Juyang

182

Alamethicin in lipid bilayers: Combined use of X-ray scattering and MD simulations Jianjun Pan a  

E-Print Network [OSTI]

Alamethicin in lipid bilayers: Combined use of X-ray scattering and MD simulations Jianjun Pan of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA d Canadian Neutron Beam Centre:1PC with varying amounts of alamethicin (Alm). We combine the use of X-ray diffuse scattering

Nagle, John F.

183

Re-analysis of Magic Angle Spinning Nuclear Magnetic Resonance Determination of Interlamellar Waters in Lipid Bilayer Dispersions  

E-Print Network [OSTI]

Re-analysis of Magic Angle Spinning Nuclear Magnetic Resonance Determination of Interlamellar Waters in Lipid Bilayer Dispersions John F. Nagle,*# Yufeng Liu,* Stephanie Tristram-Nagle,# Richard M of multilamellar lipid vesicles using magic angle spinning nuclear magnetic resonance has been re

Nagle, John F.

184

Luminescence in Mn-doped CdS nanocrystals  

Science Journals Connector (OSTI)

We have synthesized Mn-doped CdS nanocrystals (NCs) with size ranging from ... nm. Photoluminescence (PL) spectra of the doped NCs differ from that of the undoped...d-d...transitions. Electron paramagnetic resona...

Angshuman Nag; Sameer Sapra; Subhra Sen Gupta…

2008-06-01T23:59:59.000Z

185

First Principles Prediction of Nitrogen-doped Carbon Nanotubes...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

First Principles Prediction of Nitrogen-doped Carbon Nanotubes as a High-Performance Cathode for Li-S Batteries. First Principles Prediction of Nitrogen-doped Carbon Nanotubes as a...

186

Structure, Magnetism and Conductivity in Epitaxial Ti-doped ...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Magnetism and Conductivity in Epitaxial Ti-doped -Fe2O3 Hematite: Experiment and density functional theory Structure, Magnetism and Conductivity in Epitaxial Ti-doped -Fe2O3...

187

Femtosecond accumulated photon echo in Er-doped fibers  

Science Journals Connector (OSTI)

We report the observation of accumulated photon echo in Er-doped fibers. We also demonstrate time reversal and autoconvolution of femtosecond pulses, which suggest that Er-doped fibers...

da Silva, V L; Silberberg, Y; Heritage, J P; Chase, E W; Saifi, M A; Andrejco, M J

1991-01-01T23:59:59.000Z

188

Conductivity of Oriented Samaria-Doped Ceria Thin Films Grown...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Conductivity of Oriented Samaria-Doped Ceria Thin Films Grown by Oxygen-plasma-assisted Molecular Beam Epitaxy. Conductivity of Oriented Samaria-Doped Ceria Thin Films Grown by...

189

Charge neutrality in heavily doped emitters Jesus A. del Alamo  

E-Print Network [OSTI]

of a typical solar-cell emitter, being particularly excellent in the heavily doped regions beneath the surface

del Alamo, Jesús A.

190

Highly photosensitive properties of CdS thin films doped with boron in high doping levels  

Science Journals Connector (OSTI)

We report the photosensitive properties of CdS thin films doped with boron at high doping levels. Boron-doped CdS thin films were successfully prepared through the chemical bath deposition (CBD) method. The photosensitive properties of the boron-doped CdS thin films were significantly affected by the molar ratio of boric acid (H3BO3) to cadmium acetate (CdAc2) (0.001, 0.1, 0.15, and 0.25) and by NH3 concentration (7 and 14 M). As the H3BO3/CdAc2 molar ratio increased, dark sheet resistance rapidly increased, and the boron-doped CdS thin film exhibited the highest room temperature photosensitivity (?1×106 at 0.15–0.25 H3BO3/CdAc2 molar ratio). The photosensitive properties of the boron-doped CdS thin films were much higher than those previously reported in boron-doped CdS systems.

Kiran Kumar Challa; Edoardo Magnone; Eui-Tae Kim

2012-01-01T23:59:59.000Z

191

Effects of different laser sources and doping methods used to dope silicon carbide  

Science Journals Connector (OSTI)

An excimer laser and Nd:YAG laser were chosen to dope SiC polytypes by nitrogen (n-type dopant) and aluminum (p-type dopant). In the case of p-type doping, three different doping methods, i.e., (i) doping from trimethylaluminum (TMA) precursor, (ii) an effusion–diffusion process and (iii) doping from Al powder precursor, were used and compared. The results show that Nd:YAG laser treatment provides higher dopant concentration and deeper dopant penetration depth than the excimer laser treatment for both nitrogen and aluminum dopants. This difference is attributed to different heating mechanisms for the two kinds of laser sources. In the case of p-type doping by excimer laser, the Al dopant concentration distributions along the depth of wafer are different for the three doping methods. Method 3 produces the highest Al concentration, which is related to the high concentration of Al due to the formation of a molten aluminum film at the wafer surface. The Al concentration obtained by the effusion–diffusion process (method 2) is higher than that obtained by the TMA precursor method due to a higher Si vacancy concentration created by the effusion process. Shallow and deep junctions fabricated by an excimer laser and a Nd:YAG laser can be used for different semiconductor devices.

Z. Tian; I.A. Salama; N.R. Quick; A. Kar

2005-01-01T23:59:59.000Z

192

Doped luminescent materials and particle discrimination using same  

DOE Patents [OSTI]

Doped luminescent materials are provided for converting excited triplet states to radiative hybrid states. The doped materials may be used to conduct pulse shape discrimination (PSD) using luminescence generated by harvested excited triplet states. The doped materials may also be used to detect particles using spectral shape discrimination (SSD).

Doty, F. Patrick; Allendorf, Mark D; Feng, Patrick L

2014-10-07T23:59:59.000Z

193

Compact, stable 1 ghz femtosecond er-doped fiber lasers  

E-Print Network [OSTI]

We demonstrate a high-repetition-rate soliton fiber laser that is based on highly-doped anomalously-dispersive erbium-doped fiber. By splicing an 11-mm single mode fiber to the erbium-doped fiber, thermal damage of the ...

Byun, Hyunil

194

Eribium Doped Y2O3  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Effect of Local Coordination on the Photoluminescence Properties of Er-doped Effect of Local Coordination on the Photoluminescence Properties of Er-doped Y2O3 Thin Films Miniaturizing the erbium-doped optical fiber amplifier (~20 m in length) into a small, compact amplifier that can be integrated with other optical and electronic devices on a single chip (optoelectronics) offers great promise in optical communication as an alternative to the electronic technology.1,2, The gain of these miniaturized devices is limited by the solubility, concentration, and distribution of optically-active Er3+ in a host material. 3 While incorporation of a high concentration of erbium is possible by ion implantation, the method does not allow for the control of spatial distribution or the activation of the ions in the host. This is critical at high Er concentrations, since non-radiative processes resulting from ion-ion interactions become dominant and significantly reduce the photoluminescence (PL) yield.

195

Raman spectra of bilayer graphene covered with Poly(methyl methacrylate) thin film  

SciTech Connect (OSTI)

The Raman spectra of bilayer graphene covered with poly(methyl methacrylate) (PMMA) were investigated. Both the G and 2D peaks of PMMA-coated graphene were stiff and broad compared with those of uncovered graphene. This could be attributed to the residual strain induced by high-temperature baking during fabrication of the nanodevice. Furthermore, the two 2D peaks stiffened and broadened with increasing laser power, which is just the reverse to uncovered graphene. The stiffness is likely caused by graphene compression induced by the circular bubble of the thin PMMA film generated by laser irradiation. Our findings may contribute to the application of PMMA in the strain engineering of graphene nanodevices.

Xia Minggang [MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi'an Jiaotong University, 710049 (China); Center on Experimental Physics, School of Science, Xi'an Jiaotong University, 710049 (China); Su Zhidan; Zhang Shengli [MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi'an Jiaotong University, 710049 (China); Department of Applied Physics, School of Science, Xi'an Jiaotong University, 710049 (China)

2012-09-15T23:59:59.000Z

196

Full control of magnetism in a manganite bilayer by ferroelectric polarization  

SciTech Connect (OSTI)

An oxide heterostructure made of manganite bilayers and ferroelectric perovskites is predicted to lead to the full control of magnetism when switching the ferroelectric polarizations. By using asymmetric polar interfaces in the superlattices, more electrons occupy the Mn layer at the n-type interface side than at the p-type side. This charge disproportionation can be enhanced or suppressed by the ferroelectric polarization. Quantum model and density functional theory calculations reach the same conclusion: a ferromagnetic-ferrimagnetic phase transition with maximal change >90% of the total magnetization can be achieved by switching the polarization s direction. This function is robust and provides full control of the magnetization s magnitude, not only its direction, via electrical methods.

Dong, Shuai [Southeast University, Nanjing, China] [Southeast University, Nanjing, China; Dagotto, Elbio R [ORNL] [ORNL

2013-01-01T23:59:59.000Z

197

Phenomenological model for a novel melt-freeze phase of sliding bilayers  

E-Print Network [OSTI]

Simulations show that sliding bilayers of colloidal particles can exhibit a new phase, the ``melt-freeze'' phase, where the layers stochastically alternate between solidlike and liquidlike states. We introduce a mean field phenomenological model with two order parameters to understand the interplay of two adjacent layers while the system is in this remarkable phase. Predictions from our numerical simulations of a system in the melt-freeze phase include the tendency of two adjacent layers to be in opposite states (solid and liquid) and the difference between the fluctuation of the order parameter in one layer while the other layer is in the same phase compared to the fluctuation while the other layer is in the opposite phase. We expect this behavior to be seen in future simulations and experiments.

Trieu Mai

2006-01-31T23:59:59.000Z

198

Magnetic structure in Fe/Sm-Co exchange spring bilayers with intermixed interfaces.  

SciTech Connect (OSTI)

The depth profile of the intrinsic magnetic properties in an Fe/Sm-Co bilayer fabricated under nearly optimal spring-magnet conditions was determined by complementary studies of polarized neutron reflectometry and micromagnetic simulations. We found that at the Fe/Sm-Co interface, the magnetic properties change gradually at the length scale of 8 nm. In this intermixed interfacial region, the saturation magnetization and magnetic anisotropy are lower and the exchange stiffness is higher than values estimated from the model based on a mixture of Fe and Sm-Co phases. Therefore, the intermixed interface yields superior exchange coupling between the Fe and Sm-Co layers, but at the cost of average magnetization.

Liu, Y.; te Velthuis, S. G. E.; Jiang, J. S.; Choi, Y.; Bader, S. D.; Parizzi, A. A.; Ambaye, H.; Lauter, V. (Materials Science Division); (ORNL)

2011-05-06T23:59:59.000Z

199

Magnetization reversal in CoPt(111) hard/soft bilayers  

SciTech Connect (OSTI)

The magnetization reversal in magnetron sputtered CoPt(111) hard/soft bilayers has been studied by polarized neutron reflectometry and magnetization measurements. The stability of the hard layer is tuned by the heat-treatment conditions which are used to crystallize the chemically ordered, high anisotropy, L{sub 1}0 phase. All the samples show the same features in their first order reversal curves but the lateral domain size during the magnetization reversal of the soft layer differs. In samples with strong intergrain coupling it exceeds the coherence length of the neutron beam, resulting in spin-flip scattering. In contrast, the hard layer reversal occurs through the reorientation in small domains.

Alexandrakis, V.; Niarchos, D. [IMS, NCSR 'Demokritos', Ag. Paraskevi Attiki, Attiki 153 10 (Greece); Wolff, M. [Institute for Solid State Physics/EP IV, Ruhr-University Bochum, 44780 Bochum (Germany); Panagiotopoulos, I. [Department of Materials Science and Engineering, University of Ioannina, Ioannina 45110 (Greece)

2009-03-15T23:59:59.000Z

200

Sputtered Molybdenum Bilayer Back Contact for Copper Indium Diselenide-Based Polycrystalline Thin-Film Solar Cells  

E-Print Network [OSTI]

grown CdS layer followed by an ion- beam-sputtered, lightly doped (50 nm) then heavily doped (300 nm), n with the CIS at 600°C.13 glass Mo CIGS Al-Ni grid n+ ZnO i ZnO CdS sunlight MgF 2 FIG. 1. Cross-sectional view

Scofield, John H.

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Self-activating and doped tantalate phosphors.  

SciTech Connect (OSTI)

An ideal red phosphor for blue LEDs is one of the biggest challenges for the solid-state lighting industry. The appropriate phosphor material should have good adsorption and emission properties, good thermal and chemical stability, minimal thermal quenching, high quantum yield, and is preferably inexpensive and easy to fabricate. Tantalates possess many of these criteria, and lithium lanthanum tantalate materials warrant thorough investigation. In this study, we investigated red luminescence of two lithium lanthanum tantalates via three mechanisms: (1) Eu-doping, (2) Mn-doping and (3) self-activation of the tantalum polyhedra. Of these three mechanisms, Mn-doping proved to be the most promising. These materials exhibit two very broad adsorption peaks; one in the UV and one in the blue region of the spectrum; both can be exploited in LED applications. Furthermore, Mn-doping can be accomplished in two ways; ion-exchange and direct solid-state synthesis. One of the two lithium lanthanum tantalate phases investigated proved to be a superior host for Mn-luminescence, suggesting the crystal chemistry of the host lattice is important.

Nyman, May Devan; Rohwer, Lauren Elizabeth Shea

2011-01-01T23:59:59.000Z

202

Laser doping of silicon carbide substrates  

Science Journals Connector (OSTI)

A direct-write laser conversion technique was used to produce n-type and p-type doped tracks on SiC substrates. Polycrystalline and single-crystal SiC substrates were investigated. The tracks irradiated in an ...

I. A. Salama; N. R. Quick; A. Kar

2002-01-01T23:59:59.000Z

203

Geometry of hydrogen bonds formed by lipid bilayer nitroxide probes : A high frequency pulsed ENDOR/EPR study.  

SciTech Connect (OSTI)

Solvent effects on magnetic parameters of nitroxide spin labels in combination with side-directed spin-labeling EPR methods provide very useful means for elucidating polarity profiles in lipid bilayers and mapping local electrostatic effects in complex biomolecular systems. One major contributor to these solvent effects is the hydrogen bonds that could be formed between the nitroxide moiety and water and/or the available hydroxyl groups. Here, formation of hydrogen bonds between a lipid bilayer spin probe 5-doxyl stearic acid, 5DSA and hydrogen-bond donors has been studied using high-frequency (HF) pulsed ENDOR and EPR. A hydrogen-bonded deuteron was directly detected in HF ENDOR (130 GHz) spectra of 5DSA dissolved in several deuterated alcohols, while the characteristic signal was absent in nonpolar toluene-d{sub 8}. The length of the hydrogen bond, 1.74 {+-} 0.06 {angstrom}, and its geometry were found to be essentially the same for all four alcohols studied, indicating that nearly identical hydrogen bonds have been formed regardless of the solvent dielectric constant. This strengthens a hypothesis that HF EPR spectra are exclusively sensitive to formation of hydrogen bonds and could be used for probing the hydrogen-bond network in complex biomolecular assemblies and lipid bilayers with site-directed spin-labeling methods.

Smirnova, T. I.; Smirnov, A. I.; Pachtchenko, S.; Poluektov, O. G.; Chemistry; North Carolina State Univ.

2007-01-01T23:59:59.000Z

204

Initial reactions in Ti{endash}Si bilayers: New indications from in situ measurements  

SciTech Connect (OSTI)

The interactions occurring in a Ti{endash}Si bilayer have been investigated by in situ resistance measurements and the reaction products have been analyzed by complementary techniques, such as x-ray diffraction, Auger electron spectroscopy, and MeV {sup 4}He{sup +} Rutherford backscattering. The measurements were performed by heating the samples at a constant rate in the 5{endash}425{degree}C/min range. The samples are 60 nm of titanium sputter deposited on 250 nm of a silicon film deposited by chemical vapor technique; the bilayers were placed on 650 nm of SiO{sub 2}, thermally grown on p-type {l_angle}100{r_angle} silicon wafers. Samples were also prepared by reactively depositing 25 nm of TiN on the Ti film. The TiN cap, deposited without breaking the vacuum, protects the metal films from contaminants, namely oxygen, during handling and heat treatments. It has been shown that, at temperatures around 400{degree}C and before any massive Ti{endash}Si interaction, the resistance increases. This effect, attributed in the literature to the silicon diffusion in the metal film, is due to oxygen, generally contained in the annealing ambient, which diffuses in the Ti film. The Ti{endash}Si reaction produces a decrease in the value of resistance; the first decrease, generally attributed to the formation of a C49{endash}TiSi{sub 2} phase, is due to the growth of an amorphous compound having a graded in-depth composition between Ti{sub 5}Si{sub 3} and TiSi. The activation energy for such formation is 2.8{+-}0.1 eV. At higher temperatures C49{endash}TiSi{sub 2} starts to form, more likely between the silicon and the amorphous layer. The formation of silicide induces a segregation of oxygen in the unreacted Ti film, thus slowing down the growth of silicide. {copyright} 2001 American Institute of Physics.

Cocchi, R.; Giubertoni, D.; Ottaviani, G.; Marangon, T.; Mastracchio, G.; Queirolo, G.; Sabbadini, A.

2001-06-01T23:59:59.000Z

205

The Synthesis of Ag-Doped Mesoporous TiO2 . | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The Synthesis of Ag-Doped Mesoporous TiO2 . The Synthesis of Ag-Doped Mesoporous TiO2 . Abstract: Ag-doped mesoporous titanium oxide was prepared using non-ionic surfactants and...

206

The Synthesis of Cadmium Doped Mesoporous TiO2. | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The Synthesis of Cadmium Doped Mesoporous TiO2. The Synthesis of Cadmium Doped Mesoporous TiO2. Abstract: Cd doped mesoporous titanium oxide was prepared using non-ionic...

207

Substrate and method for the formation of continuous magnesium diboride and doped magnesium diboride wire  

DOE Patents [OSTI]

A chemically doped boron coating is applied by chemical vapor deposition to a silicon carbide fiber and the coated fiber then is exposed to magnesium vapor to convert the doped boron to doped magnesium diboride and a resultant superconductor.

Suplinskas, Raymond J. (Haverhill, MA); Finnemore, Douglas (Ames, IA); Bud'ko, Serquei (Ames, IA); Canfield, Paul (Ames, IA)

2007-11-13T23:59:59.000Z

208

Topological Response Theory of Doped Topological Insulators  

Science Journals Connector (OSTI)

We generalize the topological response theory of three-dimensional topological insulators (TI) to metallic systems—specifically, doped TI with finite bulk carrier density and a time-reversal symmetry breaking field near the surface. We show that there is an inhomogeneity-induced Berry phase contribution to the surface Hall conductivity that is completely determined by the occupied states and is independent of other details such as band dispersion and impurities. In the limit of zero bulk carrier density, this intrinsic surface Hall conductivity reduces to the half-integer quantized surface Hall conductivity of TI. Based on our theory we predict the behavior of the surface Hall conductivity for a doped topological insulator with a top gate, which can be directly compared with experiments.

Maissam Barkeshli and Xiao-Liang Qi

2011-11-07T23:59:59.000Z

209

Quantum radiations from exciton condensate in Electron-Hole Bilayer Systems  

E-Print Network [OSTI]

Superfluid has been realized in Helium-4, Helium-3 and ultra-cold atoms. It has been widely used in making high-precision devices and also in cooling various systems. There have been extensive experimental search for possible exciton superfluid (ESF) in semiconductor electron-hole bilayer (EHBL) systems below liquid Helium temperature. However, exciton superfluid are meta-stable and will eventually decay through emitting photons. Here we study quantum nature of photons emitted from the excitonic superfluid (ESF) phase in the semiconductor EHBL and find that the light emitted from the excitonic superfluid has unique and unusual features not shared by any other atomic or condensed matter systems. We show that the emitted photons along the direction perpendicular to the layer are in a coherent state, those along all tilted directions are in a two modes squeezed state. We determine the two mode squeezing spectra, the angle resolved power spectrum, the line shapes of both the momentum distribution curve (MDC) and the energy distribution curve (EDC). From the two photon correlation functions, we find there are photon bunching, the photo-count statistics is super-Poissonian. We discuss how several important parameters such as the chemical potential, the exciton decay rate, the quasiparticle energy spectrum and the dipole-dipole interaction strength between the excitons in our theory can be extracted from the experimental data and comment on available experimental data on both EDC and MDC.

Jinwu Ye; T. Shi; Longhua Jiang; C. P. Sun

2008-02-07T23:59:59.000Z

210

Sandwich beam model for free vibration analysis of bilayer graphene nanoribbons with interlayer shear effect  

SciTech Connect (OSTI)

In this study, sandwich beam model (SM) is proposed for free vibration analysis of bilayer graphene nanoribbons (BLGNRs) with interlayer shear effect. This model also takes into account the intralayer (in-plane) stretch of graphene nanoribbons. The molecular dynamics (MD) simulations using the software LAMMPS and Adaptive Intermolecular Reactive Empirical Bond Order (AIREBO) potential are done to validate the accuracy of the sandwich model results. The MD simulation results include the two first frequencies of cantilever BLGNRs with different lengths and two interlayer shear moduli, i.e., 0.25 and 4.6?GPa. These two interlayer shear moduli, 0.25 and 4.6?GPa, can be obtained by sliding a small flake of graphene on a large graphene substrate when the parameter of E-LJ term in AIREBO potential, epsilon-CC, is set to be 2.84 and 45.44?meV, respectively. The SM results for a wide range of bending rigidity values show that the proposed model, i.e., the SM, predicts much better than the previous beam model in which the intralayer stretch is ignored. In addition, it is observed that the model can properly predict the natural frequencies of BLGNRs for various values of the bending rigidity and the interlayer shear modulus.

Nazemnezhad, Reza, E-mail: rnazemnezhad@iust.ac.ir, E-mail: rnazemnezhad@du.ac.ir [School of Mechanical Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of); Shokrollahi, Hassan [School of Mechanical Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Hosseini-Hashemi, Shahrokh [School of Mechanical Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of); Center of Excellence in Railway Transportation, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of)

2014-05-07T23:59:59.000Z

211

Asymmetric Electron Transport at Monolayer-Bilayer Heterojunctions of Epitaxial Graphene  

SciTech Connect (OSTI)

The symmetry of the graphene honeycomb lattice is a key element determining many of graphene s unique electronic properties, such as the linear energy-momentum dispersion and the suppressed backscattering 1,2. However, line defects in large-scale epitaxial graphene films, such as grain boundaries, edges, surface steps, and changes in layer thickness, often break the sublatttice symmetry and can impact transport properties of graphene profoundly 3-6. Here we report asymmetric electron transport upon polarity reversal at individual monolayer-bilayer (ML-BL) boundaries in epitaxial graphene on SiC (0001), revealed by scanning tunneling potentiometry. A greater voltage drop is observed when the current flows from BL to ML graphene than in the reverse direction, and the difference remains nearly unchanged with increasing current. This is not a typical nonlinear conductance due to electron transmission through an asymmetric potential. Rather, it indicates the opening of a dynamic energy gap at the Fermi energy due to the Coulomb interaction between the injected nonequilibrium electron density and the pseudospin polarized Friedel oscillation charge density at the boundary. This intriguing heterojunction transport behavior opens a new avenue towards novel quantum functions such as quantum switching.

Li, An-Ping [ORNL] [ORNL; Clark, Kendal W [ORNL] [ORNL; Zhang, Xiaoguang [ORNL] [ORNL; Gu, Gong [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK); He, Guowei [Carnegie Mellon University (CMU)] [Carnegie Mellon University (CMU); Feenstra, Randall [Carnegie Mellon University (CMU)] [Carnegie Mellon University (CMU)

2014-01-01T23:59:59.000Z

212

Influence of Si Co-doping on electrical transport properties of magnesium-doped boron nanoswords  

SciTech Connect (OSTI)

Magnesium-doped boron nanoswords were synthesized via a thermoreduction method. The as-prepared nanoswords are single crystalline and {beta}-rhombohedral ({beta}-rh) phase. Electrical transport measurements show that variable range hopping conductivity increases with temperature, and carrier mobility has a greater influence than carrier concentration. These results are consistent with the three dimensional Mott's model (M. Cutler and N. F. Mott, Phys. Rev. 181, 1336 (1969)) besides a high density of localized states at the Fermi level compared with bulk {beta}-rh boron. Conductivity of Mg-doped boron nanoswords is significantly lower than that of ''pure'' (free of magnesium) boron nanoswords. Electron energy loss spectroscopy studies confirm that the poorer conductivity arises from silicon against magnesium doping.

Tian Yuan; Lu Hongliang; Tian Jifa; Li Chen; Hui Chao; Shi Xuezhao; Huang Yuan; Shen Chengmin; Gao Hongjun [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2012-03-05T23:59:59.000Z

213

Lithium/Sulfur Batteries Based on Doped Mesoporous Carbon - Energy...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Materials Advanced Materials Find More Like This Return to Search LithiumSulfur Batteries Based on Doped Mesoporous Carbon Oak Ridge National Laboratory Contact ORNL About...

214

Hole doping in high temperature superconductors using the XANES technique  

E-Print Network [OSTI]

Hole doping in high temperature superconductors using the1994 Thallium-Based High Temperature Superconductors ed A M1994 Thallium-Based High Temperature Superconductors ed A M

Hamdan, Nasser

2012-01-01T23:59:59.000Z

215

Bose Glass of Quasiparticles in Doped Quantum Magnet Gregory...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bose Glass of Quasiparticles in Doped Quantum Magnet Gregory S. Boebinger, National High Magnetic Field Laboratory DMR-Award 0654118 High BT Facility & Pulsed Field Facility When...

216

Dye-Doped Silica Nanoparticle Labels/Protein Microarray for Detection...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Dye-Doped Silica Nanoparticle LabelsProtein Microarray for Detection of Protein Biomarkers. Dye-Doped Silica Nanoparticle LabelsProtein Microarray for Detection of Protein...

217

E-Print Network 3.0 - al-doped zinc oxide Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

magnetic semiconductors 3,4. In particular, transpar- ent conductive oxide (TCO) electrodes using Al-doped... - electronic devices, we investigated aluminum-doped...

218

Raman Measurements on Electrochemically Doped Single-Walled Carbon Nanotubes  

E-Print Network [OSTI]

Raman Measurements on Electrochemically Doped Single-Walled Carbon Nanotubes P. M. Rafailov, M and studied the Raman response of electro- chemically doped single-walled carbon nanotubes (SWNT) using different salt solutions. The fre- quency shift of the radial breathing mode (RBM) and the high-energy mode

Nabben, Reinhard

219

Ionized impurity scattering in periodically ?-doped InP  

Science Journals Connector (OSTI)

The quantum mobility in the individual minibands of InP with periodic Si ? doping was estimated from the Shubnikov–de Haas spectra of the samples, measured at 4.2 K in fields of 0–14 T. The set of samples studied had a sheet density of Si atoms of about 4.9×1012 cm-2 in each doped layer, and a doping period in the range 90–300 ?. A theoretical model for the quantum mobility in individual minibands was developed, and theoretical estimates of the quantum mobility are in reasonable agreement with the experimental values. It is observed that at a fixed doping period the quantum mobilities increase with the index of the miniband, and the quantum mobility in an individual miniband decreases when the doping period is made shorter. The dependence of the quantum mobility on the miniband index and doping periodicity correlates with the dependence of the mean distance between electrons and the doped layer on the same quantities. These results demonstrate that in ?-doped semiconductors the binding length of the quantum-confined electronic charge is a very important parameter, determining the carrier mobility which can be attained in these systems.

A. B. Henriques, L. C. D. Gon?calves, N. F. Oliveira Jr., P. L. Souza, and B. Yavich

1997-05-15T23:59:59.000Z

220

Superlattice doped layers for amorphous silicon photovoltaic cells  

DOE Patents [OSTI]

Superlattice doped layers for amorphous silicon photovoltaic cells comprise a plurality of first and second lattices of amorphous silicon alternatingly formed on one another. Each of the first lattices has a first optical bandgap and each of the second lattices has a second optical bandgap different from the first optical bandgap. A method of fabricating the superlattice doped layers also is disclosed.

Arya, Rajeewa R. (Doylestown, PA)

1988-01-12T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Controllable N-Doping of Graphene Beidou Guo,,  

E-Print Network [OSTI]

Controllable N-Doping of Graphene Beidou Guo,, Qian Liu, Erdan Chen, Hewei Zhu, Liang Fang in graphene are central to many electronic applications of graphene. Here we report N-doped graphene obtained by NH3 annealing after N+ -ion irradiation of graphene samples. First, the evolution of the graphene

Gong, Jian Ru

222

Femtosecond Laser Ablation of Silicon: Nanoparticles, Doping and Photovoltaics  

E-Print Network [OSTI]

Femtosecond Laser Ablation of Silicon: Nanoparticles, Doping and Photovoltaics A thesis presented Laser Ablation of Silicon: Nanoparticles, Doping and Photovoltaics Eric Mazur Brian R. Tull Abstract irradiated surface layer to the grain boundaries. #12;iv Lastly, we measure the photovoltaic properties

Mazur, Eric

223

Two-oscillator model of trapped-modes interaction in a nonlinear bilayer fish-scale metamaterial  

E-Print Network [OSTI]

We discuss the similarity between the nature of resonant oscillations in two nonlinear systems, namely, a chain of coupled Duffing oscillators and a bilayer fish-scale metamaterial. In such systems two different resonant states arise which differ in their spectral lines. The spectral line of the first resonant state has a Lorentzian form, while the second one has a Fano form. This difference leads to a specific nonlinear response of the systems which manifests itself in appearance of closed loops in spectral lines and bending and overlapping of resonant curves. Conditions of achieving bistability and multistability are found out.

Tuz, Vladimir R; Kochetova, Lyudmila A; Mladyonov, Pavel L; Prosvirnin, Sergey L

2014-01-01T23:59:59.000Z

224

Nitrogen doped zinc oxide thin film  

SciTech Connect (OSTI)

To summarize, polycrystalline ZnO thin films were grown by reactive sputtering. Nitrogen was introduced into the films by reactive sputtering in an NO{sub 2} plasma or by N{sup +} implantation. All ZnO films grown show n-type conductivity. In unintentionally doped ZnO films, the n-type conductivities are attributed to Zn{sub i}, a native shallow donor. In NO{sub 2}-grown ZnO films, the n-type conductivity is attributed to (N{sub 2}){sub O}, a shallow double donor. In NO{sub 2}-grown ZnO films, 0.3 atomic % nitrogen was found to exist in the form of N{sub 2}O and N{sub 2}. Upon annealing, N{sub 2}O decomposes into N{sub 2} and O{sub 2}. In furnace-annealed samples N{sub 2} redistributes diffusively and forms gaseous N{sub 2} bubbles in the films. Unintentionally doped ZnO films were grown at different oxygen partial pressures. Zni was found to form even at oxygen-rich condition and led to n-type conductivity. N{sup +} implantation into unintentionally doped ZnO film deteriorates the crystallinity and optical properties and leads to higher electron concentration. The free electrons in the implanted films are attributed to the defects introduced by implantation and formation of (N{sub 2}){sub O} and Zni. Although today there is still no reliable means to produce good quality, stable p-type ZnO material, ZnO remains an attractive material with potential for high performance short wavelength optoelectronic devices. One may argue that gallium nitride was in a similar situation a decade ago. Although we did not obtain any p-type conductivity, we hope our research will provide a valuable reference to the literature.

Li, Sonny X.

2003-12-15T23:59:59.000Z

225

Scintillation of rare earth doped fluoride nanoparticles  

SciTech Connect (OSTI)

The scintillation response of rare earth (RE) doped core/undoped (multi-)shell fluoride nanoparticles was investigated under x-ray and alpha particle irradiation. A significant enhancement of the scintillation response was observed with increasing shells due: (i) to the passivation of surface quenching defects together with the activation of the REs on the surface of the core nanoparticle after the growth of a shell, and (ii) to the increase of the volume of the nanoparticles. These results are expected to reflect a general aspect of the scintillation process in nanoparticles, and to impact radiation sensing technologies that make use of nanoparticles.

Jacobsohn, L. G.; McPherson, C. L.; Sprinkle, K. B.; Ballato, J. [Center for Optical Materials Science and Engineering Technologies (COMSET), and School of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634 (United States); Yukihara, E. G. [Physics Department, Oklahoma State University, Stillwater, Oklahoma 74078-3072 (United States); DeVol, T. A. [Department of Environmental Engineering and Earth Sciences, Clemson University, Clemson, South Carolina 29634-0905 (United States)

2011-09-12T23:59:59.000Z

226

Proton conductivity of potassium doped barium zirconates  

SciTech Connect (OSTI)

Potassium doped barium zirconates have been synthesized by solid state reactions. It was found that the solubility limit of potassium on A-sites is between 5% and 10%. Introducing extra potassium leads to the formation of second phase or YSZ impurities. The water uptake of barium zirconates was increased even with 5% doping of potassium at the A-site. The sintering conditions and conductivity can be improved significantly by adding 1 wt% ZnO during material synthesis. The maximum solubility for yttrium at B-sites is around 15 at% after introducing 1 wt% zinc. The conductivity of Ba{sub 0.95}K{sub 0.05}Zr{sub 0.85}Y{sub 0.11}Zn{sub 0.04}O{sub 3-{delta}} at 600 deg. C is 2.2x10{sup -3} S/cm in wet 5% H{sub 2}. The activation energies for bulk and grain boundary are 0.29(2), 0.79(2) eV in wet 5% H{sub 2} and 0.31(1), 0.74(3) eV in dry 5% H{sub 2}. A power density of 7.7 mW/cm{sup 2} at 718 deg. C was observed when a 1 mm thick Ba{sub 0.95}K{sub 0.05}Zr{sub 0.85}Y{sub 0.11}Zn{sub 0.04}O{sub 3-{delta}} pellet was used as electrolyte and platinum electrodes. - Graphical abstract: Potassium doped barium zirconates have been synthesized by solid state reactions. It was found that the solubility limit of potassium on A-sites is between 5% and 10 %. The sintering conditions and conductivity can be improved significantly by adding 1 wt% ZnO during material synthesis. Five percent doping of potassium at A-site can double the total conductivity.

Xu Xiaoxiang [School of Chemistry, University of St. Andrews, Fife KY16 9ST (United Kingdom); Tao Shanwen, E-mail: s.tao@hw.ac.u [School of Chemistry, University of St. Andrews, Fife KY16 9ST (United Kingdom); Department of Chemistry, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Irvine, John T.S. [School of Chemistry, University of St. Andrews, Fife KY16 9ST (United Kingdom)

2010-01-15T23:59:59.000Z

227

IR permittivities for silicides and doped silicon  

SciTech Connect (OSTI)

The complex permittivity for Pt, Pd, Ni, and Ti-silicide films as well as heavily doped p- and n-type silicon were determined by ellipsometry over the energy range 0.031 eV to 4.0 eV. Fits to the Drude model gave bulk plasma and relaxation frequencies. Rutherford backscattering spectroscopy, X-ray diffraction, scanning electron microscopy, secondary ion mass spectrometry, and four-point probe measurements complemented the optical characterization. Calculations from measured permittivities of waveguide loss and mode confinement suggest that the considered materials are better suited for long-wavelength surface-plasmon-polariton waveguide applications than metal films.

Cleary, J. W.; Peale, R. E.; Smith, C. W.; Ishigami, M. [Department of Physics, University of Central Florida, Orlando, Florida 32816 (United States); Shelton, D. J.; Boreman, G. D. [College of Optics (CREOL), University of Central Florida, Orlando, Florida 32816 (United States); Soref, R.; Drehman, A.; Buchwald, W. R. [Sensors Directorate, Air Force Research Laboratory, Hanscom Air Force Base, Massachusetts 01731 (United States)

2010-04-15T23:59:59.000Z

228

LASER TRANSFER DOPING USING AMORPHOUS SILICON Rafel Ferr (Correspondence author)1  

E-Print Network [OSTI]

LASER TRANSFER DOPING USING AMORPHOUS SILICON Rafel Ferré (Correspondence author)1 , Ralf Gogolin1@isfh.de ABSTRACT: We demonstrate and characterize "Laser Transfer Doping" (LTD) for producing locally doped regions. For this purpose we use nanosecond pulsed laser for transferring phosphorus doped amorphous silicon from a carrier

229

Color stable manganese-doped phosphors  

DOE Patents [OSTI]

A process for preparing color stable Mn.sup.+4 doped phosphors includes providing a phosphor of formula I; A.sub.x[MF.sub.y]:Mn.sup.+4 I and contacting the phosphor in particulate form with a saturated solution of a composition of formula II in aqueous hydrofluoric acid; A.sub.x[MF.sub.y]; II wherein A is Li, Na, K, Rb, Cs, NR.sub.4 or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; R is H, lower alkyl, or a combination thereof; x is the absolute value of the charge of the [MF.sub.y] ion; and y is 5, 6 or 7. In particular embodiments, M is Si, Ge, Sn, Ti, Zr, or a combination thereof. A lighting apparatus capable of emitting white light includes a semiconductor light source; and a phosphor composition radiationally coupled to the light source, and which includes a color stable Mn.sup.+4 doped phosphor.

Lyons, Robert Joseph (Burnt Hills, NY); Setlur, Anant Achyut (Niskayuna, NY); Deshpande, Anirudha Rajendra (Twinsburg, OH); Grigorov, Ljudmil Slavchev (Sofia, BG)

2012-08-28T23:59:59.000Z

230

Tunneling magnetoresistance tuned by a vertical electric field in an AA-stacked graphene bilayer with double magnetic barriers  

SciTech Connect (OSTI)

We investigate the effect of a vertical electric field on the electron tunneling and magnetoresistance in an AA-stacked graphene bilayer modulated by the double magnetic barriers with parallel or antiparallel configuration. The results show that the electronic transmission properties in the system are sensitive to the magnetic-barrier configuration and the bias voltage between the graphene layers. In particular, it is found that for the antiparallel configuration, within the low energy region, the blocking effect is more obvious compared with the case for the parallel configuration, and even there may exist a transmission spectrum gap which can be arbitrarily tuned by the field-induced interlayer bias voltage. We also demonstrate that the significant discrepancy between the conductance for both parallel and antiparallel configurations would result in a giant tunneling magnetoresistance ratio, and further the maximal magnetoresistance ratio can be strongly modified by the interlayer bias voltage. This leads to the possible realization of high-quality magnetic sensors controlled by a vertical electric field in the AA-stacked graphene bilayer.

Wang, Dali, E-mail: wangdali@mail.ahnu.edu.cn [Department of Physics and Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000 (China); National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093 (China); Jin, Guojun, E-mail: gjin@nju.edu.cn [National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093 (China)

2013-12-21T23:59:59.000Z

231

Step-edge-induced resistance anisotropy in quasi-free-standing bilayer chemical vapor deposition graphene on SiC  

SciTech Connect (OSTI)

The transport properties of quasi-free-standing (QFS) bilayer graphene on SiC depend on a range of scattering mechanisms. Most of them are isotropic in nature. However, the SiC substrate morphology marked by a distinctive pattern of the terraces gives rise to an anisotropy in graphene's sheet resistance, which may be considered an additional scattering mechanism. At a technological level, the growth-preceding in situ etching of the SiC surface promotes step bunching which results in macro steps ?10?nm in height. In this report, we study the qualitative and quantitative effects of SiC steps edges on the resistance of epitaxial graphene grown by chemical vapor deposition. We experimentally determine the value of step edge resistivity in hydrogen-intercalated QFS-bilayer graphene to be ?190???m for step height h{sub S}?=?10?nm and provide proof that it cannot originate from mechanical deformation of graphene but is likely to arise from lowered carrier concentration in the step area. Our results are confronted with the previously reported values of the step edge resistivity in monolayer graphene over SiC atomic steps. In our analysis, we focus on large-scale, statistical properties to foster the scalable technology of industrial graphene for electronics and sensor applications.

Ciuk, Tymoteusz [Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw (Poland); Institute of Microelectronics and Optoelectronics, Warsaw University of Technology, Koszykowa 75, 00-662 Warsaw (Poland); Cakmakyapan, Semih; Ozbay, Ekmel [Department of Electrical and Electronics Engineering, Department of Physics, Nanotechnology Research Center, Bilkent University, 06800 Bilkent, Ankara (Turkey); Caban, Piotr; Grodecki, Kacper; Pasternak, Iwona; Strupinski, Wlodek, E-mail: wlodek.strupinski@itme.edu.pl [Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw (Poland); Krajewska, Aleksandra [Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw (Poland); Institute of Optoelectronics, Military University of Technology, Gen. S. Kaliskiego 2, 00-908 Warsaw (Poland); Szmidt, Jan [Institute of Microelectronics and Optoelectronics, Warsaw University of Technology, Koszykowa 75, 00-662 Warsaw (Poland)

2014-09-28T23:59:59.000Z

232

Green-Yellow Electroluminescence from a host-dopant blended system as the active layer in a bilayer polymer light emitting diode: Poly(n-vinyl carbazole) as the host and a new soluble thiophene based copolymer [poly(2,2?-BT)-co-(3-DDT)] as the dopant  

Science Journals Connector (OSTI)

Abstract A new type of bilayer Polymer Light Emitting Diode (PLED) which emits green-yellow light is reported. In this PLED, a novel thiophene-based copolymer [poly(2,2?-BT)-co-(3-DDT)] with an excellent electron transporting property has been doped in hole transporting and electron blocking poly(n-vinylcarbazole) (PVK). Formation of type-II heterojunctions among nm-size features in PVK:poly(2,2?-BT)-co-(3-DDT) blended system makes exciplex and electroplex emissions would be dominant in the Electroluminescence (EL) spectrum of the device. These cross recombinations between electrons in the LUMO of poly(2,2?-BT)-co-(3-DDT) and holes in the HOMO of PVK is a reason for the low driving voltage of the PLED because there is no need for the charge carriers to hop or tunnel to the adjacent polymer. Morphological investigations demonstrate that the mixing degree between the components is high, favoring formation of exciplexes and electroplexes at the interface of the components.

Afshin Shahalizad; Sohrab Ahmadi-Kandjani; Hossein Movla; Hafez Omidi; Bakhshali Massoumi; Mohammad Sadegh Zakerhamidi; Ali Akbar Entezami

2014-01-01T23:59:59.000Z

233

On the Inner Structure and Topology of Clusters in Two-Component Lipid Bilayers. Comparison of Monomer and Dimer Ising Models  

Science Journals Connector (OSTI)

Comparison of Monomer and Dimer Ising Models ... Clusters of two-component phospholipid bilayers have been simulated by two Ising-type lattice models: the monomer and the dimer model. ... The first theoretical model of a collective system, the model of ferromagnets, was developed by Ernst Ising(17) in 1925. ...

István P. Sugár

2008-08-26T23:59:59.000Z

234

CVD Growth of Mono-and Bi-Layer Graphene from Ethanol Xiao Chen, Pei Zhao, Bo Hou, Erik Einarsson, Shohei Chiashi and Shigeo Maruyama  

E-Print Network [OSTI]

CVD Growth of Mono- and Bi-Layer Graphene from Ethanol Xiao Chen, Pei Zhao, Bo Hou, Erik Einarsson precursors have been employed to synthesize graphene, such as methane [6], ethane [7] and ethanol [8]. Here we report a systematic study on CVD growth of graphene on Cu and Ni substrates from ethanol. Ethanol

Maruyama, Shigeo

235

P solid-state NMR studies of the dependence of inter-bilayer water dynamics on lipid headgroup structure and membrane peptides  

E-Print Network [OSTI]

2D 1 H­31 P solid-state NMR studies of the dependence of inter-bilayer water dynamics on lipid Revised 29 September 2008 Available online 5 October 2008 Keywords: Water Lipid membranes Solid-state NMR headgroup structure and membrane peptides Tim Doherty, Mei Hong * Department of Chemistry, Iowa State

Hong, Mei

236

Water-Protein Interactions of an Arginine-Rich Membrane Peptide in Lipid Bilayers Investigated by Solid-State Nuclear Magnetic Resonance Spectroscopy  

E-Print Network [OSTI]

from water to proteins.1 For microcrystalline proteins in the solid-state, magic-angle- spinning (MASWater-Protein Interactions of an Arginine-Rich Membrane Peptide in Lipid Bilayers Investigated by Solid-State Nuclear Magnetic Resonance Spectroscopy Shenhui Li, Yongchao Su, Wenbin Luo, and Mei Hong

Hong, Mei

237

3>2>1: Investigation of Single Particle Particle and Many Body Physics in Dual-Gated 1,2,3 Layers of Graphene  

E-Print Network [OSTI]

to the VI profile of Josephson junctions. At the largest B,projects on suspended Josephson junctions and effects ofgraphene-based Josephson junction. Such a system has been

Velasco, Jairo

2012-01-01T23:59:59.000Z

238

Phase diagram of half-doped manganites  

Science Journals Connector (OSTI)

The phase diagram of half-doped manganites which may consist of experimentally observed ferromagnetic (FM), A-,C-, and charge-exchange (CE)-type antiferromagnetic (AF) states is obtained in terms of a model which is based on double exchange via degenerate eg orbitals, the on-site Coulomb interaction (U), and the nearest-neighbor Coulomb interaction (V). We find that, because of the strong spatial anisotropy of the electron hoppings, the on-site Coulomb interaction has different effects on these magnetic order states. As a result, large values of U suppress the FM state and favor the A- and C-type AF states. Moreover, we show that it is the interplay between the on-site and nearest-neighbor Coulomb repulsions that stabilizes the CE phase and results in the charge ordering in the state.

Zhenghuang Shu; Jinming Dong; D. Y. Xing

2001-05-18T23:59:59.000Z

239

Luminescence of Cds Nanoparticles Doped with Silver Ions  

Science Journals Connector (OSTI)

The optical characteristics of CdS nanoparticles doped with silver ions and produced in aqueous...+...ions in the composition of the semiconductor nanoparticles at which it is possible to increase their luminesce...

G. Ya. Grodzyuk; V. V. Shvalagin; S. R. Lavorik…

2014-09-01T23:59:59.000Z

240

Self-doping effects in epitaxially grown graphene  

E-Print Network [OSTI]

The electronic properties of graphene, Rev. Mod. Phys. (inE?ects in Epitaxially-Grown Graphene D.A. Siegel, 1, 2 S.Y.2009) Abstract Self-doping in graphene has been studied by

Siegel, David A.

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Laser annealing of neutron irradiated boron-10 isotope doped diamond  

Science Journals Connector (OSTI)

10B isotope doped p-type diamond epilayer grown by chemical vapor deposition on (110) oriented type IIa diamond single crystal substrate was subjected to neutron transmutation at a fluence of 2.4...

K. Jagannadham; M. J. Lance; J. E. Butler

2011-04-01T23:59:59.000Z

242

Multimode cladding-pumped erbium-doped fibre laser  

SciTech Connect (OSTI)

A multimode cladding-pumped erbium-doped fibre laser is described. The maximum output power and the slope efficiency of the laser at 1.6 {mu}m are 4.2 W and 30%, respectively. (fibre lasers)

Kurkov, Andrei S; Paramonov, Vladimir M [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Yashkov, M V [Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation); Goncharov, S E; Zalevskii, I D [Milon Group, Moscow (Russian Federation)

2007-04-30T23:59:59.000Z

243

Calculations of the electronic structure of doped Buckminsterfullerene  

Science Journals Connector (OSTI)

Molecular cluster calculations within the local density approximation have been performed in a study of the electronic structure of theC 60 molecule — “Buckminsterfullerene” doped with different a...

D. Östling; A. Rosén

1993-01-01T23:59:59.000Z

244

Magnetic properties of doped GdI2  

Science Journals Connector (OSTI)

...Motivated by the recent experimental studies on layered ferromagnetic metallic system GdI2??and its doped variant GdI2Hx?we develop a model to understand their ground state magnetic phase diagram. Based on fi...

T. Maitra; A. Taraphder; A. N. Yaresko…

2006-02-01T23:59:59.000Z

245

Doubly Doped Nanocrystals DOI: 10.1002/ange.201100464  

E-Print Network [OSTI]

, Mn2+ -doped CdS[17] and ZnS[18,19] NCs with white-light emission have been successfully prepared of semiconductor NCs with white-light emission such as "magic-sized" CdSe NCs,[1] trap-rich CdS-QDs and onionDoubly Doped Nanocrystals DOI: 10.1002/ange.201100464 Bright White-Light Emitting Manganese

Demir, Hilmi Volkan

246

Doped carbon nanostructure field emitter arrays for infrared imaging  

DOE Patents [OSTI]

An infrared imaging device and method for making infrared detector(s) having at least one anode, at least one cathode with a substrate electrically connected to a plurality of doped carbon nanostructures; and bias circuitry for applying an electric field between the anode and the cathode such that when infrared photons are adsorbed by the nanostructures the emitted field current is modulated. The detectors can be doped with cesium to lower the work function.

Korsah, Kofi (Knoxville, TN) [Knoxville, TN; Baylor, Larry R (Farragut, TN) [Farragut, TN; Caughman, John B (Oak Ridge, TN) [Oak Ridge, TN; Kisner, Roger A (Knoxville, TN) [Knoxville, TN; Rack, Philip D (Knoxville, TN) [Knoxville, TN; Ivanov, Ilia N (Knoxville, TN) [Knoxville, TN

2009-10-27T23:59:59.000Z

247

Excitons in a mirror: Formation of “optical bilayers” using MoS{sub 2} monolayers on gold substrates  

SciTech Connect (OSTI)

We report coupling of excitons in monolayers of molybdenum disulphide to their mirror image in an underlying gold substrate. Excitons at the direct band gap are little affected by the substrate whereas strongly bound C-excitons associated with a van-Hove singularity change drastically. On quartz substrates only one C-exciton is visible (in the blue) but on gold substrates a strong red-shifted extra resonance in the green is seen. Exciton coupling to its image leads to formation of a “mirror biexciton” with enhanced binding energy. Estimates of this energy shift in an emitter-gold system match experiments well. The absorption spectrum of MoS{sub 2} on gold thus resembles a bilayer of MoS{sub 2} which has been created by optical coupling. Additional top-mirrors produce an “optical bulk.”.

Mertens, Jan; Baumberg, Jeremy J., E-mail: jjb12@cam.ac.uk [Nanophotonics Centre, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom); Shi, Yumeng; Yang, Hui Ying, E-mail: yanghuiying@sutd.edu.sg [Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore 138682 (Singapore); Molina-Sánchez, Alejandro; Wirtz, Ludger [Physics and Materials Science Research Unit, University of Luxembourg, L-1511 Luxembourg (Luxembourg)

2014-05-12T23:59:59.000Z

248

Feasibility of study magnetic proximity effects in bilayer 'superconductor/ferromagnet' using waveguide-enhanced polarized neutron reflectometry  

SciTech Connect (OSTI)

A resonant enhancement of the neutron standing waves is proposed to use in order to increase the magnetic neutron scattering from a 'superconductor/ferromagnet' (S/F) bilayer. The model calculations show that usage of this effect allows to increase the magnetic scattering intensity by factor of hundreds. Aspects related to the growth procedure (order of deposition, roughness of the layers etc.) as well as experimental conditions (resolution, polarization of the neutron beam, background etc) are also discussed. Collected experimental data for the S/F heterostructure Cu(32 nm)/V(40 nm)/Fe(1 nm)/MgO confirmed the presence of a resonant 60-fold amplification of the magnetic scattering.

Khaydukov, Yu. N., E-mail: khaiduk@nf.jinr.ru; Nikitenko, Yu. V. [Joint Institute for Nuclear Research (Russian Federation); Bottyan, L. [Research Institute for Particle and Nuclear Physics (Hungary); Ruehm, A. [Max-Planck-Institut fuer Metallforschung (Germany); Aksenov, V. L. [Joint Institute for Nuclear Research (Russian Federation)

2010-12-15T23:59:59.000Z

249

Trench process and structure for backside contact solar cells with polysilicon doped regions  

DOE Patents [OSTI]

A solar cell includes polysilicon P-type and N-type doped regions on a backside of a substrate, such as a silicon wafer. An interrupted trench structure separates the P-type doped region from the N-type doped region in some locations but allows the P-type doped region and the N-type doped region to touch in other locations. Each of the P-type and N-type doped regions may be formed over a thin dielectric layer. Among other advantages, the resulting solar cell structure allows for increased efficiency while having a relatively low reverse breakdown voltage.

De Ceuster, Denis; Cousins, Peter John; Smith, David D

2014-03-18T23:59:59.000Z

250

Trench process and structure for backside contact solar cells with polysilicon doped regions  

DOE Patents [OSTI]

A solar cell includes polysilicon P-type and N-type doped regions on a backside of a substrate, such as a silicon wafer. An interrupted trench structure separates the P-type doped region from the N-type doped region in some locations but allows the P-type doped region and the N-type doped region to touch in other locations. Each of the P-type and N-type doped regions may be formed over a thin dielectric layer. Among other advantages, the resulting solar cell structure allows for increased efficiency while having a relatively low reverse breakdown voltage.

De Ceuster, Denis; Cousins, Peter John; Smith, David D

2013-05-28T23:59:59.000Z

251

Color stable manganese-doped phosphors  

DOE Patents [OSTI]

A lighting apparatus capable of emitting white light includes a semiconductor light source; and a phosphor material radiationally coupled to the light source. The phosphor material includes a color-stable Mn.sup.+4 doped phosphor prepared by a process including providing a phosphor of formula I; A.sub.x[MF.sub.y]:Mn.sup.+4 I and contacting the phosphor in particulate form with a saturated solution of a composition of formula II in aqueous hydrofluoric acid; A.sub.x[MF.sub.y]; II wherein A is Li, Na, K, Rb, Cs, NR.sub.4 or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; R is H, lower alkyl, or a combination thereof; x is the absolute value of the charge of the [MF.sub.y] ion; and y is 5, 6 or 7. In particular embodiments, M is Si, Ge, Sn, Ti, Zr, or a combination thereof.

Lyons, Robert Joseph; Setlur, Anant Achyut; Deshpande, Anirundha Rajendra; Grigorov, Ljudmil Slavchev

2014-04-29T23:59:59.000Z

252

Mesoporous Nanostructured Nb-Doped Titanium Dioxide Microsphere Catalyst Supports for PEM Fuel Cell Electrodes  

Science Journals Connector (OSTI)

Mesoporous Nanostructured Nb-Doped Titanium Dioxide Microsphere Catalyst Supports for PEM Fuel Cell Electrodes ... The material has been investigated as cathode electrocatalyst support for polymer electrolyte membrane (PEM) fuel cells. ... doped titania; PEMFC; electrocatalyst; mesoporous materials; microspheres ...

Laure Chevallier; Alexander Bauer; Sara Cavaliere; Rob Hui; Jacques Rozière; Deborah J. Jones

2012-03-19T23:59:59.000Z

253

Synthesis Of Nitrogen-Doped Graphene Films For Lithium Battery Application  

Science Journals Connector (OSTI)

Synthesis Of Nitrogen-Doped Graphene Films For Lithium Battery Application ... Fabrication of Nitrogen-Doped Holey Graphene Hollow Microspheres and Their Use as an Active Electrode Material for Lithium Ion Batteries ...

Arava Leela Mohana Reddy; Anchal Srivastava; Sanketh R. Gowda; Hemtej Gullapalli; Madan Dubey; Pulickel M. Ajayan

2010-10-08T23:59:59.000Z

254

Synthesis of Room-Temperature Ferromagnetic Cr-doped TiO(110...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Ferromagnetic Cr-doped TiO(110) Rutile Single Crystals using Ion Implantation. Synthesis of Room-Temperature Ferromagnetic Cr-doped TiO(110) Rutile Single Crystals using Ion...

255

In Situ One-Step Synthesis of Hierarchical Nitrogen-Doped Porous...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

One-Step Synthesis of Hierarchical Nitrogen-Doped Porous Carbon for High Performance Supercapacitors. In Situ One-Step Synthesis of Hierarchical Nitrogen-Doped Porous Carbon for...

256

Iron (III) Chloride doping of large-area chemical vapor deposition graphene  

E-Print Network [OSTI]

Chemical doping is an effective method of reducing the sheet resistance of graphene. This thesis aims to develop an effective method of doping large area Chemical Vapor Deposition (CVD) graphene using Iron (III) Chloride ...

Song, Yi, S.M. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

257

Manipulation of half-metallicity and ferromagnetism in N-doped CdS nanowire  

Science Journals Connector (OSTI)

The spin-polarization and magnetic coupling of N-doped CdS nanowires (NWs) with a diameter size ... been investigated through first-principles calculations. The doped N prefers surface S sites and leads ... The r...

Fu-bao Zheng; Chang-wen Zhang; Shi-shen Yan; Feng Li

2013-04-01T23:59:59.000Z

258

Solvothermally synthesized europium-doped CdS nanorods: applications as phosphors  

Science Journals Connector (OSTI)

To exploit the photoluminescent behavior of CdS at nanoscale with different doping concentration of europium—a rare earth element, we report the synthesis of Eu-doped CdS nanorods by using low temperature solvoth...

Sunil Kumar; Zinki Jindal; Nitu Kumari…

2011-10-01T23:59:59.000Z

259

Undoped and indium-doped CdS films prepared by chemical vapour deposition  

Science Journals Connector (OSTI)

Undoped and In-doped films of CdS were deposited at different temperatures by the ... and good adherence to the substrate. The doped films have higher electron mobility values compared ... (Moss-Burstein effect) ...

G. Meyer; J. Saura

1993-10-01T23:59:59.000Z

260

Photoelectric properties of pure and aluminium doped CdS films  

Science Journals Connector (OSTI)

Photoelectric properties of pure and Al doped vacuum deposited CdS films have been studied to explore the ... rate of deposition and the extent of Al doping, etc. on the resistivity, photo-response ... has been f...

S Jatar; A C Rastogi; V G Bhide

1978-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Soft X-Ray Spectroscopic Study of Dense Strontium-Doped Lanthanum...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Soft X-Ray Spectroscopic Study of Dense Strontium-Doped Lanthanum Manganite Cathodes for Solid Oxide Fuel Cell Applications. Soft X-Ray Spectroscopic Study of Dense Strontium-Doped...

262

The influence of index-depressions in core-pumped Yb-doped large pitch fibers  

Science Journals Connector (OSTI)

Rare-earth doped photonic crystal fibers rely ideally on an index matching of the doped core to the surrounding glass to work properly. Obtaining a perfect index matching is...

Jansen, Florian; Stutzki, Fabian; Otto, Hans-Jürgen; Baumgartl, Martin; Jauregui, Cesar; Limpert, Jens; Tünnermann, Andreas

2010-01-01T23:59:59.000Z

263

Electrical properties of Er-doped In0.53Ga0.47As  

E-Print Network [OSTI]

semiconductors doped with rare- earth elements is of signi?applications. 4 However, rare-earth elements, such as Er,pos- sibility of using rare-earth elements for doping narrow

2011-01-01T23:59:59.000Z

264

Influence of samaria doping on the resistance of ceria thin films...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

doping on the resistance of ceria thin films and its implications to the planar oxygen sensing devices. Influence of samaria doping on the resistance of ceria thin films and...

265

Growth of Cr-doped TiO Films in the Rutile and Anatase Structures...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of Cr-doped TiO Films in the Rutile and Anatase Structures by Oxygen Plasma Assisted Molecular Beam Epitaxy . Growth of Cr-doped TiO Films in the Rutile and Anatase Structures by...

266

ChemFeeds -The targeted delivery of multicomponent cargos to cancer cells by nanoporous particle-supported lipid bilayers http://www.chemfeeds.com/comments.php?doi=10.1038/nmat2992[4/21/2011 11:45:43 AM  

E-Print Network [OSTI]

-supported lipid bilayers http://www.chemfeeds.com/comments.php?doi=10.1038/nmat2992[4/21/2011 11:45:43 AM] New by nanoporous particle-supported lipid bilayers http://www.chemfeeds.com/comments.php?doi=10.1038/nmat2992 to cancer cells by nanoporous particle-supported lipid bilayers http://www.chemfeeds.com/comments.php?doi=10

Brinker, C. Jeffrey

267

Effects of hydrochloric acid treatment of TiO{sub 2} nanoparticles/nanofibers bilayer film on the photovoltaic properties of dye-sensitized solar cells  

SciTech Connect (OSTI)

Highlights: ? The TiO{sub 2} nanoparticles/TiO{sub 2} nanofibers bilayer film was fabricated for DSSC. ? The effects of HCl treated TiO{sub 2} on the performance of DSSC were investigated. ? The potential methods of improving conversion efficiency are suggested. - Abstract: The TiO{sub 2} nanoparticles/nanofibers bilayer film has been fabricated via spin coating and electrospinning followed by calcination. The TiO{sub 2} bilayer film with thickness of about 6.0 ?m is composed of anatase TiO{sub 2} phase. Dye-sensitized solar cells (DSSC) were assembled by hydrochloric acid (HCl) treated TiO{sub 2} film. The results of the photocurrent action spectra, electrochemical impedance spectroscopy (EIS), and I–V curves showed that each photovoltaic parameter of DSSC increased with the concentration of HCl increasing, and reached a maximum value and afterwards decreased. The maximum incident monochromatic photo-to-electron conversion efficiency (at 350 nm) and maximum overall conversion efficiency (?) of 0.05 M HCl treated TiO{sub 2} based DSSC were enhanced to 48.0% and 4.75%, which were respectively increased by 14% and 6.3% than those of DSSC based on untreated TiO{sub 2} film.

Song, Lixin; Du, Pingfan; Shao, Xiaoli; Cao, Houbao; Hui, Quan [Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Xiong, Jie, E-mail: jxiong@zstu.edu.cn [Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018 (China)

2013-03-15T23:59:59.000Z

268

Phase transformation and crystallization kinetics of a-Ge/Cu bilayer for blue-ray recording under thermal annealing and pulsed laser irradiation  

SciTech Connect (OSTI)

Similar phase formation and crystallization behaviors have been observed in the a-Ge/Cu bilayer under thermal annealing and pulsed laser irradiation. The Cu{sub 3}Ge phase would form prior to the crystallization of a-Ge. The crystallization temperature and activation energy for crystallization of a-Ge were reduced to 310 deg. C and 2.75 eV, respectively, due to the fast Ge diffusion in the already formed germanide phases. The reaction exponent m of {approx}2.0 for the a-Ge/Cu bilayer corresponds to a crystallization process in which grain growth occurs with nucleation, and the nucleation rate decreases with the progress of the grain growth process. Under pulsed laser irradiation, the maximum data-transfer-rates of 44, 56, 74, and 112 Mbit/s can be achieved in the write-once blue-ray disk at the recording powers of 3, 4, 5, and 6 mW, respectively. The a-Ge/Cu bilayer also demonstrated sufficient optical contrast and adequate absorptance for low power and high speed write-once blue-ray recording.

Her, Yung-Chiun; Tu, Wei-Ting; Tsai, Ming-Hsin [Department of Materials Science and Engineering, National Chung Hsing University, Taichung, Taiwan 40254 (China)

2012-02-15T23:59:59.000Z

269

Synthesis of na-doped lithium metatitanate and its absorption for carbon dioxide  

Science Journals Connector (OSTI)

Na-doped lithium metatitanate (Na-doped Li2TiO3) absorbent was doped with Na2CO3 and lithium metatitanate (Li2TiO3) was prepared by a solid-state reaction method from mixture of TiO2 ...

Liu Zhirong, Zhang Huan, Wang Yun, Zhan Xinxing

2014-01-01T23:59:59.000Z

270

COMMUNICATIONS Cd doping at the CuInSe2 CdS heterojunction  

E-Print Network [OSTI]

COMMUNICATIONS Cd doping at the CuInSe2 �CdS heterojunction Dongxiang Liaoa) and Angus Rockett that CIGS could be doped with Cd during chemical bath deposition CBD of CdS.6 However, Cd doping of CIGS October 2002; accepted 7 March 2003 The chemical composition of the CuInSe2 /CdS heterojunction interface

Rockett, Angus

271

Performance study of CdS/Co-Doped-CdSe quantum dot sensitized solar cells  

Science Journals Connector (OSTI)

In order to optimize the charge transfer path in quantum dot sensitized solar cells (QDSCs), we employed successive ionic layer adsorption and reaction method to dope CdSe with Co for fabricating CdS/Co-doped-CdSe QDSCs constructed with CdS/Co-doped-CdSe ...

Xiaoping Zou, Sheng He, Gongqing Teng, Chuan Zhao

2014-01-01T23:59:59.000Z

272

Chemical Preparation of Pure and Strontium-and/or Magnesium-Doped Lanthanum Gallate Powders  

E-Print Network [OSTI]

Chemical Preparation of Pure and Strontium- and/or Magnesium-Doped Lanthanum Gallate Powders A. Cu) ceramics that have been doped with strontium and/or magnesium are known to have superior oxygen re- cently synthesized strontium- and magnesium-doped LaGaO3 ceramics, using the conventional "solid

Tas, A. Cuneyt

273

Comparison study of biomimetic strontium-doped calcium phosphate coatings by electrochemical deposition and air plasma  

E-Print Network [OSTI]

Comparison study of biomimetic strontium-doped calcium phosphate coatings by electrochemical April 2012 Ã? Springer Science+Business Media, LLC 2012 Abstract In this study, strontium-doped calcium of the strontium-doped calcium phosphate coatings were evaluated using bone cell culture using MC3T3-E1 osteoblast

Meng, Yizhi

274

Passively harmonic mode locked erbium doped fiber soliton laser with carbon nanotubes based  

E-Print Network [OSTI]

Passively harmonic mode locked erbium doped fiber soliton laser with carbon nanotubes based. Tokumoto, H. Kataura, and Y. Achiba, "Sub-200-fs pulsed erbium- doped fiber laser using a carbon nanotube fs erbium-doped fiber laser mode locked with a cellulose polymer film containing single-wall carbon

Turitsyn, Sergei K.

275

Hafnium-doped tantalum oxide high-k gate dielectric films for future CMOS technology  

E-Print Network [OSTI]

of the doped films were explained by their compositions and bond structures. The Hf-doped TaOx film is a potential high-k gate dielectric for future MOS transistors. A 5 Ã?Â? tantalum nitride (TaNx) interface layer has been inserted between the Hf-doped Ta...

Lu, Jiang

2007-04-25T23:59:59.000Z

276

Doping mechanisms in graphene-MoS{sub 2} hybrids  

SciTech Connect (OSTI)

We present a joint theoretical and experimental investigation of charge doping and electronic potential landscapes in hybrid structures composed of graphene and semiconducting single layer molybdenum disulfide (MoS{sub 2}). From first-principles simulations, we find electron doping of graphene due to the presence of rhenium impurities in MoS{sub 2}. Furthermore, we show that MoS{sub 2} edges give rise to charge reordering and a potential shift in graphene, which can be controlled through external gate voltages. The interplay of edge and impurity effects allows the use of the graphene-MoS{sub 2} hybrid as a photodetector. Spatially resolved photocurrent signals can be used to resolve potential gradients and local doping levels in the sample.

Sachs, B., E-mail: bsachs@physnet.uni-hamburg.de; Lichtenstein, A. I. [I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, D-20355 Hamburg (Germany)] [I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, D-20355 Hamburg (Germany); Britnell, L.; Eckmann, A.; Novoselov, K. S. [School of Physics and Astronomy, University of Manchester, M13 9PL Manchester (United Kingdom)] [School of Physics and Astronomy, University of Manchester, M13 9PL Manchester (United Kingdom); Wehling, T. O. [Institut für Theoretische Physik, Universität Bremen, Otto-Hahn-Allee 1, D-28359 Bremen (Germany) [Institut für Theoretische Physik, Universität Bremen, Otto-Hahn-Allee 1, D-28359 Bremen (Germany); Bremen Center for Computational Materials Science, Universität Bremen, Am Fallturm 1a, D-28359 Bremen (Germany); Jalil, R.; Belle, B. D. [Manchester Centre for Mesoscience and Nanotechnology, University of Manchester, Manchester M13 9PL (United Kingdom)] [Manchester Centre for Mesoscience and Nanotechnology, University of Manchester, Manchester M13 9PL (United Kingdom); Katsnelson, M. I. [Institute for Molecules and Materials, Radboud University of Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen (Netherlands)] [Institute for Molecules and Materials, Radboud University of Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen (Netherlands)

2013-12-16T23:59:59.000Z

277

Theory of the spontaneous buckling of doped graphene  

E-Print Network [OSTI]

Graphene is a realization of an esoteric class of materials -- electronic crystalline membranes. We study the interplay between the free electrons and the two-dimensional crystal, and find that it induces a substantial effect on the elastic structure of the membrane. For the hole-doped membrane, in particular, we predict a spontaneous buckling. In addition, attenuation of elastic waves is expected, due to the effect of corrugations on the bulk modulus. These discoveries have a considerable magnitude in graphene, affecting both its mesoscopic structure, and its electrical resistivity, which has an inherent asymmetry between hole- and electron-doped graphene.

Doron Gazit

2008-10-06T23:59:59.000Z

278

Engineering shallow spins in diamond with nitrogen delta-doping  

SciTech Connect (OSTI)

We demonstrate nanometer-precision depth control of nitrogen-vacancy (NV) center creation near the surface of synthetic diamond using an in situ nitrogen delta-doping technique during plasma-enhanced chemical vapor deposition. Despite their proximity to the surface, doped NV centers with depths (d) ranging from 5 to 100 nm display long spin coherence times, T{sub 2} > 100 {mu}s at d = 5 nm and T{sub 2} > 600 {mu}s at d {>=} 50 nm. The consistently long spin coherence observed in such shallow NV centers enables applications such as atomic-scale external spin sensing and hybrid quantum architectures.

Ohno, Kenichi; Joseph Heremans, F.; Bassett, Lee C.; Myers, Bryan A.; Toyli, David M.; Bleszynski Jayich, Ania C.; Palmstrom, Christopher J.; Awschalom, David D. [Center for Spintronics and Quantum Computation, University of California, Santa Barbara, California 93106 (United States)

2012-08-20T23:59:59.000Z

279

Nanosecond molecular relaxations in lipid bilayers studied by high energy resolution neutron scattering and in-situ diffraction  

E-Print Network [OSTI]

We report a high energy-resolution neutron backscattering study to investigate slow motions on nanosecond time scales in highly oriented solid supported phospholipid bilayers of the model system DMPC -d54 (deuterated 1,2-dimyristoyl-sn-glycero-3-phoshatidylcholine), hydrated with heavy water. Wave vector resolved quasi-elastic neutron scattering (QENS) is used to determine relaxation times $\\tau$, which can be associated with different molecular components, i.e., the lipid acyl chains and the interstitial water molecules in the different phases of the model membrane system. The inelastic data are complemented both by energy resolved and energy integrated in-situ diffraction. From a combined analysis of the inelastic data in the energy and time domain, the respective character of the relaxation, i.e., the exponent of the exponential decay is also determined. From this analysis we quantify two relaxation processes. We associate the fast relaxation with translational diffusion of lipid and water molecules while the slow process likely stems from collective dynamics.

Maikel C. Rheinstädter; Tilo Seydel; Tim Salditt

2006-07-20T23:59:59.000Z

280

Hole superconductivity in the electron-doped superconductor Pr2?xCexCuO4  

Science Journals Connector (OSTI)

We measure the resistivity and Hall angle of the electron-doped superconductor Pr2?xCexCuO4 as a function of doping and temperature. The resistivity ?xx at temperatures 100Kdoping independent over a wide doping range and even for nonsuperconducting samples. On the other hand, the transverse resistivity ?xy, or the Hall angle ?H, where cot(?H)=?xx??xy, is sensitive to both holes and electrons. Its temperature dependence is strongly influenced by doping, and cot(?H) can be used to identify optimum doping (the maximum Tc) even well above the critical temperature. These results lead to a conclusion that in electron doped cuprates holes are responsible for the superconductivity.

Y. Dagan and R. L. Greene

2007-07-11T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Ultralow Thermal Conductivity of Isotope-Doped Silicon Nanowires  

E-Print Network [OSTI]

conductivity of SiNWs is about 2 orders of magnitude smaller than that of bulk crystals.18,19 The low thermal conductivity (0.05 W/m K) found in layered materials.22 So it is indispensable to reduce the thermal conUltralow Thermal Conductivity of Isotope-Doped Silicon Nanowires Nuo Yang, Gang Zhang,*, and Baowen

Li, Baowen

282

Improving Platinum Catalyst Durability with a Doped Graphene Support  

Science Journals Connector (OSTI)

Improving the durability of a platinum catalyst is an important step in increasing its utility when incorporated as the anode or cathode of a proton-exchange membrane fuel cell. ... Carboxyl Group Enhanced CO Tolerant GO Supported Pt Catalysts: DFT and Electrochemical Analysis ... Chemical Structure of Nitrogen-Doped Graphene with Single Platinum Atoms and Atomic Clusters as a Platform for the PEMFC Electrode ...

Michael N. Groves; Cecile Malardier-Jugroot; Manish Jugroot

2012-04-13T23:59:59.000Z

283

Recombination mechanisms in highly doped CdS:In  

Science Journals Connector (OSTI)

Time-resolved luminescence measurements of CdS:In cyrstals in the near-band-gap region are presented for a wide range of indium doping levels, i.e., for concentrations between 1017 and 1020 cm-3. Interactions of the indium dopants lead to a broad luminescence band near the band-gap energy and alter the luminescence dynamics. A decrease of the lifetimes of both donor and acceptor bound exciton complexes is observed at medium doping levels (1017–1018 cm-3). This is explained by the reduction of the effective binding energies leading to shorter decay constants of these complexes. The decay of the donor-acceptor-pair recombination luminescence is also investigated for indium concentrations below the Mott density. A statistical model proposed by Thomas and Hopfield is used to determine the electronically active impurity concentration. At higher doping levels (up to 1020 cm-3) the degeneracy of the conduction band leads to a luminescence band attributed to radiative non-k-conserving band-to-band transitions. The measured lifetimes reflect the number of occupied states in the conduction band and the number of free states in the valence band. A nonexponential fit reveals the concentration of electronically active impurity centers. A correlation between photogenerated and doping-generated carriers is established for high excitation densities.

Ch. Fricke; R. Heitz; A. Hoffmann; I. Broser

1994-02-15T23:59:59.000Z

284

ACCURATE EXTRACTION OF DOPING PROFILES FROM ELECTROCHEMICAL CAPACITANCE VOLTAGE MEASUREMENTS  

E-Print Network [OSTI]

. In addition, the corrected ECV data can be precisely reproduced with the process simulation software Ssuprem3 Ohrberg 1, 31860 Emmerthal, Germany 2 Dep. Solar Energy, Inst. Solid-State Physics, Leibniz University-8]. The SIMS method is in comparison to the other methods expensive and provides only the chemical doping

285

Method of making metal-doped organic foam products  

DOE Patents [OSTI]

Organic foams having a low density and very small cell size and method for roducing same in either a metal-loaded or unloaded (nonmetal loaded) form are described. Metal-doped foams are produced by soaking a polymer gel in an aqueous solution of desired metal salt, soaking the gel successively in a solvent series of decreasing polarity to remove water from the gel and replace it with a solvent of lower polarity with each successive solvent in the series being miscible with the solvents on each side and being saturated with the desired metal salt, and removing the last of the solvents from the gel to produce the desired metal-doped foam having desired density cell size, and metal loading. The unloaded or metal-doped foams can be utilized in a variety of applications requiring low density, small cell size foam. For example, rubidium-doped foam made in accordance with the invention has utility in special applications, such as in x-ray lasers.

Rinde, James A. (Livermore, CA)

1981-01-01T23:59:59.000Z

286

High phosphorous doped germanium: Dopant diffusion and modeling  

E-Print Network [OSTI]

The in situ n-type doping of Ge thin films epitaxial grown on Si substrates is limited to 1?×?10[superscript 19]?cm[superscript ?3] by the phosphorous out-diffusion during growth at 600?°C. By studying the phosphorous ...

Cai, Yan

287

Doped Carbon Nanotubes for Hydrogen Storage Ragaiy Zidan  

E-Print Network [OSTI]

Doped Carbon Nanotubes for Hydrogen Storage Ragaiy Zidan Savannah River Technology Center Savannah-capacity hydrogen storage material. The final product should have favorable thermodynamics and kinetics- board hydrogen storage for transportation applications. One of the candidates for solid hydrogen storage

288

Properties of Heavily Doped n?Type Germanium  

Science Journals Connector (OSTI)

The electrical and optical properties of n?type germanium have been studied for doping levels greater than 5×1018 cm?3. Hall coefficient and resistivity measurements show that the electron mobility ? depends upon the specific group V donor used as a dopant and at a given carrier concentration increases in the order ?Aselementary conduction theory.

W. G. Spitzer; F. A. Trumbore; R. A. Logan

1961-01-01T23:59:59.000Z

289

Concentration efficiency of doping in phosphors: Investigation of the copper-and aluminum-doped zinc sulfide  

E-Print Network [OSTI]

Concentration efficiency of doping in phosphors: Investigation of the copper- and aluminum October 2003 We studied the effect of dopant concentration in ZnS:Cu, Al phosphor. Photoluminescent PL intensity of the chemically etched phosphor particles increased up to 140%, which proved the existence

Grujicic, Mica

290

The effect of interface oxygen content on magnetoelectric effect of epitaxial La{sub 0.7}Sr{sub 0.3}MnO{sub 3}/BaTiO{sub 3} bilayer  

SciTech Connect (OSTI)

The epitaxial La{sub 0.7}Sr{sub 0.3}MnO{sub 3}/BaTiO{sub 3} (LSMO/BTO) bilayer films are grown on (001) oriented LaAlO{sub 3} substrate by pulsed laser deposition technique. The oxygen-rich interface is obtained through in-situ annealing process in oxygen, and the oxygen-deficient interface is obtained without the annealing process. The results show that the ferromagnetic properties of the LSMO film and the magnetoelectric effect (ME) of the bilayer films strongly correlate to the oxygen content at the interface of LSMO/BTO. The saturated magnetization and the ME voltage coefficient of the oxygen-rich bilayer film are higher than that of oxygen-deficient one. It suggests a more effective ME coupling at the LSMO/BTO interface, which are generated through not only the interface strain but also the spin polarized carriers.

Tingxian, Li, E-mail: wxlltx@126.com [College of Physics and Electrical Engineering, Anyang Normal University, Anyang 455002 (China); Kuoshe, Li [National Engineering Research Central for Rare Earth Materials, General Research Institute for Nonferrous Metals, The Grirem Advanced materials Co. Ltd., Beijing 100088 (China)

2014-01-28T23:59:59.000Z

291

Excellent Passivation and Low Reflectivity Al2O3/TiO2 Bilayer Coatings for n-Wafer Silicon Solar Cells: Preprint  

SciTech Connect (OSTI)

A bilayer coating of Al2O3 and TiO2 is used to simultaneously achieve excellent passivation and low reflectivity on p-type silicon. This coating is targeted for achieving high efficiency n-wafer Si solar cells, where both passivation and anti-reflection (AR) are needed at the front-side p-type emitter. It could also be valuable for front-side passivation and AR of rear-emitter and interdigitated back contact p-wafer cells. We achieve high minority carrier lifetimes {approx}1 ms, as well as a nearly 2% decrease in absolute reflectivity, as compared to a standard silicon nitride AR coating.

Lee, B. G.; Skarp, J.; Malinen, V.; Li, S.; Choi, S.; Branz, H. M.

2012-06-01T23:59:59.000Z

292

Thermally driven asymmetric responses of grains versus spin-glass related distributions of blocking temperature in exchange biased Co/IrMn bilayers  

SciTech Connect (OSTI)

Controlling ferromagnetic/antiferromagnetic blocking temperatures in exchange biased based devices appears crucial for applications. The blocking temperature is ascribed to the ability of both antiferromagnetic grains and interfacial spin-glass-like phases to withstand ferromagnetic magnetization reversal. To better understand the respective contributions of grains versus spin-glass, blocking temperature distributions were measured after various thermal treatments for cobalt/iridium-manganese bilayers. The high-temperature contribution linked to antiferromagnetic grains shifts towards lower temperatures above a threshold thermal annealing. In contrast, the occurrence and evolution of training effects for the low-temperature contribution only agree with its inferred interfacial spin-glass-like origin.

Baltz, V. [SPINTEC, UMR 8191 CNRS/INAC-CEA/UJF-Grenoble 1/Grenoble-INP, F-38054 Cedex (France)] [SPINTEC, UMR 8191 CNRS/INAC-CEA/UJF-Grenoble 1/Grenoble-INP, F-38054 Cedex (France)

2013-02-11T23:59:59.000Z

293

Influence of damping constant on inverse spin hall voltage of La{sub 0.7}Sr{sub 0.3}MnO{sub 3}(x)/platinum bilayers  

SciTech Connect (OSTI)

Pure spin transport via spin pumping in the condition of ferromagnetic resonance can be transformed to charge current in the ferromagnetic/paramagnetic bilayer systems, based on inverse spin Hall effect (ISHE). Here, we explore La{sub 0.7}Sr{sub 0.3}MnO(x)/Pt(5.5?nm) [x?=?10 to 65 nm] bilayers to investigate the influence of damping constant on spin pumping efficiency. The results show that the ISHE voltage depend on the damping constant of magnetic moment, suggesting that the precession energy tansferred to lattice/electron of normal metal is a key parameter to control the magnitude of spin current.

Luo, G. Y. [Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan (China); Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Chang, C. R. [Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Lin, J. G., E-mail: jglin@ntu.edu.tw [Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan (China)

2014-05-07T23:59:59.000Z

294

Control of work function of graphene by plasma assisted nitrogen doping  

SciTech Connect (OSTI)

Nitrogen doping is expected to provide several intriguing properties to graphene. Nitrogen plasma treatment to defect-free and defective highly oriented pyrolytic graphite (HOPG) samples causes doping of nitrogen atom into the graphene layer. Nitrogen atoms are initially doped at a graphitic site (inside the graphene) for the defect-free HOPG, while doping to a pyridinic or a pyrrolic site (edge of the graphene) is dominant for the defective HOPG. The work function of graphene correlates strongly with the site and amount of doped nitrogen. Nitrogen atoms doped at a graphitic site lower the work function, while nitrogen atoms at a pyridinic or a pyrrolic site increase the work function. Control of plasma treatment time and the amount of initial defect could change the work function of graphite from 4.3?eV to 5.4?eV, which would open a way to tailor the nature of graphene for various industrial applications.

Akada, Keishi; Terasawa, Tomo-o; Imamura, Gaku; Obata, Seiji; Saiki, Koichiro, E-mail: saiki@k.u-tokyo.ac.jp [Department of Complexity Science and Engineering, The University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, Chiba 277-8561 (Japan)

2014-03-31T23:59:59.000Z

295

OPTICAL AND DYNAMIC PROPERTIES OF UNDOPED AND DOPED SEMICONDUCTOR NANOSTRUCTURES  

SciTech Connect (OSTI)

This chapter provides an overview of some recent research activities on the study of optical and dynamic properties of semiconductor nanomaterials. The emphasis is on unique aspects of these properties in nanostructures as compared to bulk materials. Linear, including absorption and luminescence, and nonlinear optical as well as dynamic properties of semiconductor nanoparticles are discussed with focus on their dependence on particle size, shape, and surface characteristics. Both doped and undoped semiconductor nanomaterials are highlighted and contrasted to illustrate the use of doping to effectively alter and probe nanomaterial properties. Some emerging applications of optical nanomaterials are discussed towards the end of the chapter, including solar energy conversion, optical sensing of chemicals and biochemicals, solid state lighting, photocatalysis, and photoelectrochemistry.

Grant, C D; Zhang, J Z

2007-09-28T23:59:59.000Z

296

Doped surfaces in one sun, point-contact solar cells  

SciTech Connect (OSTI)

This letter reports two new types of large-area (>8.5 cm/sup 2/), backside, point-contact solar cells with doped surfaces, designed for use in unconcentrated sunlight. One type was fabricated on an intrinsic substrate with an optimized phosphorus diffusion on the sunward surface. The apertured-area efficiency was independently measured to be 22.3% at 1 sun (0.100 W/cm/sup 2/), 25 /sup 0/C, the highest reported for a silicon solar cell. The other type is constructed on a doped substrate, and has an apertured-area efficiency of 20.9%, the highest reported for a point-contact solar cell with a base in low-level injection. Both cells have record open-circuit voltages above 700 mV.

King, R.R.; Sinton, R.A.; Swanson, R.M.

1989-04-10T23:59:59.000Z

297

Ion exchange phase transitions in "doped" water--filled channels  

E-Print Network [OSTI]

Ion transport through narrow water--filled channels is impeded by a high electrostatic barrier. The latter originates from the large ratio of the dielectric constants of the water and a surrounding media. We show that ``doping'', i.e. immobile charges attached to the walls of the channel, substantially reduces the barrier. This explains why most of the biological ion channels are ``doped''. We show that at rather generic conditions the channels may undergo ion exchange phase transitions (typically of the first order). Upon such a transition a finite latent concentration of ions may either enter or leave the channel, or be exchanged between the ions of different valences. We discuss possible implications of these transitions for the Ca-vs.-Na selectivity of biological Ca channels. We also show that transport of divalent Ca ions is assisted by their fractionalization into two separate excitations.

J. Zhang; A. Kamenev; B. I. Shklovskii

2005-10-12T23:59:59.000Z

298

Ytterbium-doped borate fluoride laser crystals and lasers  

DOE Patents [OSTI]

A new class of solid state laser crystals and lasers are formed from Yb-doped borate fluoride host crystals. The general formula for the host crystals is MM{prime}(BO{sub 3})F, where M, M{prime} are monovalent, divalent aria trivalent metal cations. A particular embodiment of the invention is Yb-doped BaCaBO{sub 3}F (Yb:BCBF). BCBF and some of the related derivative crystals are capable of nonlinear frequency conversion, whereby the fundamental of the laser is converted to a longer or shorter wavelength. In this way, these new crystals can simultaneously serve as self-frequency doubling crystals and laser materials within the laser resonator. 6 figs.

Schaffers, K.I.; DeLoach, L.D.; Payne, S.A.; Keszler, D.A.

1997-10-14T23:59:59.000Z

299

Er3+-doped Nanoparticles for Optical Detection of Magnetic Field  

Science Journals Connector (OSTI)

In this work, we have studied an effect of magnetic field up to 50 T on emission spectrum of Er3+ in Er3+-doped nanoparticles prepared by chemical etching of the respective bulk nano-glass-ceramics template and found a unique strong effect of the magnetic field on the integral intensity of the 4S3/2?4I15/2 green emission line while integral intensities of other visible emission lines were only slightly affected. ... Figure 2. 4.2 K spectra of the 4S3/2?4I15/2 luminescence band of Er3+-doped nanoparticles in different pulsed magnetic fields (pulsed field flat plateau is about 5 ms); the intensity of luminescence decreases with applied field (a). ...

Victor K. Tikhomirov; Liviu F. Chibotaru; Damien Saurel; Patrick Gredin; Michel Mortier; Victor V. Moshchalkov

2009-01-07T23:59:59.000Z

300

Method of fabricating optical waveguides by ion implantation doping  

DOE Patents [OSTI]

A method for fabricating high-quality optical waveguides in optical quality oxide crystals by ion implantation doping and controlled epitaxial recrystallization is provided. Masked LiNbO/sub 3/ crystals are implanted with high concentrations of Ti dopant at ion energies of about 360 keV while maintaining the crystal near liquid nitrogen temperature. Ion implantation doping produces an amorphous, Ti-rich nonequilibrium phase in the implanted region. Subsequent thermal annealing in a water-saturated oxygen atmosphere at up to 1000/degree/C produces solid-phase epitaxial regrowth onto the crystalline substrate. A high-quality crystalline layer results which incorporates the Ti into the crystal structure at much higher concentrations than is possible by standard diffusion techniques, and this implanted region has excellent optical waveguiding properties.

Appleton, B.R.; Ashley, P.R.; Buchal, C.J.

1987-03-24T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

High gain photoconductive semiconductor switch having tailored doping profile zones  

DOE Patents [OSTI]

A photoconductive semiconductor switch with tailored doping profile zones beneath and extending laterally from the electrical contacts to the device. The zones are of sufficient depth and lateral extent to isolate the contacts from damage caused by the high current filaments that are created in the device when it is turned on. The zones may be formed by etching depressions into the substrate, then conducting epitaxial regrowth in the depressions with material of the desired doping profile. They may be formed by surface epitaxy. They may also be formed by deep diffusion processes. The zones act to reduce the energy density at the contacts by suppressing collective impact ionization and formation of filaments near the contact and by reducing current intensity at the contact through enhanced current spreading within the zones.

Baca, Albert G. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Mar, Alan (Albuquerque, NM); Zutavern, Fred J (Albuquerque, NM); Hjalmarson, Harold P. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM); Zipperian, Thomas E. (Edgewood, NM); O'Malley, Martin W. (Edgewood, NM); Helgeson, Wesley D. (Albuquerque, NM); Denison, Gary J. (Sandia Park, NM); Brown, Darwin J. (Albuquerque, NM); Sullivan, Charles T. (Albuquerque, NM); Hou, Hong Q. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

302

Photon avalanche up-conversion in holmium doped fluoride glasses  

SciTech Connect (OSTI)

Photon avalanche green up-conversion emission centered at 545 nm has been observed in Ho{sup 3+} doped and Ho{sup 3+}, Tm{sup 3+} co-doped ZrF{sub 4}-based fluoride glasses when excited near 585 nm which is off resonance with any ground state absorption bands of either Ho{sup 3+} or Tm{sup 3+} ions. Detailed spectral measurements and analysis suggest that the 545 nm emission occurs from the {sup 5}S{sub 2},{sup 5}F{sub 4} states of Ho{sup 3+} that are populated by excited state absorption from the {sup 5}I{sub 7} state of Ho{sup 3+}. Strong cross-relaxation that efficiently populates the {sup 5}I{sub 7} state makes the photon avalanche process possible in this system.

Chen, Y.H.; Liu, G.K.; Beitz, J.V. [Argonne National Lab., IL (United States). Chemistry Division; Jie Wang [Shanghai Institute of Optics and Fine Mechanics, Shanghai (China)

1996-08-01T23:59:59.000Z

303

Delta doping of ferromagnetism in antiferromagnetic manganite superlattices.  

SciTech Connect (OSTI)

We demonstrate that delta doping can be used to create a dimensionally confined region of metallic ferromagnetism in an antiferromagnetic (AFM) manganite host, without introducing any explicit disorder due to dopants or frustration of spins. Theoretical consideration of these additional carriers shows that they cause a local enhancement of ferromagnetic double exchange with respect to AFM superexchange, resulting in local canting of the AFM spins. This leads to a highly modulated magnetization, as measured by polarized neutron reflectometry. The spatial modulation of the canting is related to the spreading of charge from the doped layer and establishes a fundamental length scale for charge transfer, transformation of orbital occupancy, and magnetic order in these manganites. Furthermore, we confirm the existence of the canted, AFM state as was predicted by de Gennes [Phys. Rev. 118 141 (1960)] but had remained elusive.

Santos, T. S.; Kirby, B. J.; Kumar, S.; May, S. J.; Borchers, J. A.; Maranville, B. B.; Zarestky, J.; te Velthuis, S. G. E.; van den Brink, J.; Bhattacharya, A. (Center for Nanoscale Materials); ( MSD); (NIST); (IFW Dresden); (Drexel Univ.); (Iowa State Univ.)

2011-01-01T23:59:59.000Z

304

INTERACTION OF DEFECTS IN CdTe-CRYSTALS HEAVILY DOPED WITH CHLORINE  

E-Print Network [OSTI]

ClTe) and (VCd 2 ClTe)] form, but larger clusters as well. Thus, the compensation process in Cl doped CdTe, PAGE In order to clarify the mechanism of compensation in semi-insulating crystals of CdTe doped.1051/rphysap:01977001202023500 #12;236 FIG. 1. - Photoluminescence spectra of In and Cl doped CdTe. ND = 10 17

Paris-Sud XI, Université de

305

Eu-doped Y2O3 nanosheets and nanotubes  

SciTech Connect (OSTI)

A hydrothermal method was used to synthesize Eu-doped Y2O3 nanosheets and nanotubes. High Resolution transmission electron microscopy (HRTEM) and synchrotron x-ray diffraction were used to characterize these nanomaterials. The nanosheets were obtained using a slightly lower pH value and they were partly crystalline and partly amorphous. Using a pH value of about 10, fully crystalline nanotubes were obtained. It is anticipated that nanosheets folded themselves to form stable nanotubes.

Sun, Hongtao [Texas Tech University, Lubbock; Chaudhari, Jharna [Texas Tech University, Lubbock; Kenik, Edward A [ORNL; Zhu, H [Texas Tech University, Lubbock; Ma, Y [Texas Tech University, Lubbock

2011-01-01T23:59:59.000Z

306

Kohn anomalies and non-adiabaticity in doped carbon nanotubes  

E-Print Network [OSTI]

The high-frequency Raman-active phonon modes of metallic single-walled carbon nanotubes (SWNTs) are thought to be characterized by Kohn anomalies (KAs), which are expected to be modified by the doping-induced tuning of the Fermi energy level $\\epsilon_F$, obtained through the intercalation of SWNTs with alkali atoms or by the application of a gate potential. We present a Density-Functional Theory (DFT) study of the phonon properties of a (9,9) metallic SWNT as a function of electronic doping. For such study, we use, as in standard DFT calculations of vibrational properties, the Born-Oppenheimer (BO) approximation. We also develop an analytical model capable of reproducing and interpreting our DFT results. Both DFT calculations and this model predict, for increasing doping levels, a series of EPC-induced KAs in the vibrational mode parallel to the tube axis at the $\\mathbf\\Gamma$ point of the Brillouin zone, usually indicated in Raman spectroscopy as the $G^-$ peak. Such KAs would arise each time a new conduction band is populated. However, we show that they are an artifact of the BO approximation. The inclusion of non-adiabatic (NA) effects dramatically affects the results, predicting KAs at $\\mathbf\\Gamma$ only when $\\epsilon_F$ is close to a band crossing $E_{X}$. For each band crossing a double KA occurs for $\\epsilon_F=E_{X}\\pm \\hbar\\omega/2$, where $\\hbar\\omega$ is the phonon energy. In particular, for a 1.2 $nm$ metallic nanotube, we predict a KA to occur in the so-called $G^-$ peak at a doping level of about $N_{el}/C=\\pm 0.0015$ atom ($\\epsilon_F\\approx \\pm 0.1 ~eV$). Furthermore, we predict that the Raman linewidth of the $G^-$ peak significantly decreases for $|\\epsilon_F| \\geq \\hbar\\omega/2$.

Nicolas Caudal; A. Marco Saitta; Michele Lazzeri; Francesco Mauri

2007-02-21T23:59:59.000Z

307

Method for measuring the drift mobility in doped semiconductors  

DOE Patents [OSTI]

A method for measuring the drift mobility of majority carriers in semiconductors consists of measuring the current transient in a Schottky-barrier device following the termination of a forward bias pulse. An example is given using an amorphous silicon hydrogenated material doped with 0.2% phosphorus. The method is particularly useful with material in which the dielectric relaxation time is shorter than the carrier transit time. It is particularly useful in material useful in solar cells. 10 figs.

Crandall, R.S.

1982-03-09T23:59:59.000Z

308

Optical Response of Shocked Cerium-Doped Lutetium Oxyorthosilicate  

SciTech Connect (OSTI)

Shock experiments were performed in order to characterize the triboluminescent signature of cerium-doped lutetium oxyorthosilicate (LSO:Ce). This material shows prompt, nano-second timescale light emission when driven by explosive detonation. When properly applied to a surface, it may be used as a shock arrival sensor, and also for imaging the propagation of a shock front. Triboluminescent rise times, spectral content, and spatial resolution measurements are presented.

G. D. Stevens

2003-03-01T23:59:59.000Z

309

Theory of nitrogen doping of carbon nanoribbons: Edge effects  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

Nitrogen doping of a carbon nanoribbon is profoundly affected by its one-dimensional character, symmetry, and interaction with edge states. Using state-of-the-art ab initio calculations, including hybrid exact-exchange density functional theory, we find that, for N-doped zigzag ribbons, the electronic properties are strongly dependent upon sublattice effects due to the non-equivalence of the two sublattices. For armchair ribbons, N-doping effects are different depending upon the ribbon family: for families 2 and 0, the N-induced levels are in the conduction band, while for family 1 the N levels are in the gap. In zigzag nanoribbons, nitrogen close to the edge is a deep center, while in armchair nanoribbons its behavior is close to an effective-mass-like donor with the ionization energy dependent on the value of the band gap. In chiral nanoribbons, we find strong dependence of the impurity level and formation energy upon the edge position of the dopant, while such site-specificity is not manifested in the magnitude of the magnetization.

Jiang, Jie [North Carolina State Univ., Raleigh, NC (United States) and Yale Univ, New Haven, CT (United States); Turnbull, Joseph [North Carolina State Univ., Raleigh, NC (United States); Lu, Wenchang [North Carolina State Univ., Raleigh, NC (United States) and Oak Ridge National Lab., TN (United States); Boguslawski, Piotr [North Carolina State Univ., Raleigh, NC (United States) and Institute of Physics, Warsaw, and Bydgoszcz (Poland); Bernholc, J. [North Carolina State Univ., Raleigh, NC (United States) and Oak Ridge National Lab., TN (United States)

2012-01-05T23:59:59.000Z

310

Plasmons in inhomogeneously doped neutral and charged graphene nanodisks  

SciTech Connect (OSTI)

We study plasmons in graphene nanodisks including the effect of inhomogeneity in the distribution of the doping charge. Specifically, we discuss the following two configurations: charged disks containing a fixed amount of additional carriers, which are self-consistently distributed along the surface to produce a uniform DC potential; and neutral disks exposed to a neighboring external point charge. A suitable finite-element method is elaborated to compute the charge density associated with the plasmons in the electrostatic limit. For charged disks, we find dipolar plasmons similar to those of uniformly doped graphene structures, in which the plasmon induced charge piles up near the edges. In contrast, in neutral disks placed near an external point charge, plasmons are strongly localized away from the edges. Surprisingly, a single external electron is enough to trap plasmons. The disks also display axially symmetric dark-plasmons, which can be excited through external illumination by coupling them to a neighboring metallic element. Our results have practical relevance for graphene nanophotonics under inhomogeneous doping conditions.

Silveiro, Iván [ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona) (Spain); Javier García de Abajo, F., E-mail: javier.garciadeabajo@icfo.es [ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona) (Spain); ICREA-Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys, 23, 08010 Barcelona (Spain)

2014-03-31T23:59:59.000Z

311

Catalyst characterisation of Fe-doped-titanium dioxide  

Science Journals Connector (OSTI)

Fe (5 wt. %) doped TiO2 was synthesised using a hydrothermal method. This material was characterised by X-Ray diffraction (XRD), Raman spectroscopy, scanning electron microscope (SEM) imaging, BET surface area, X-Ray photoelectron spectroscopy (XPS) and ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS). The BET surface area was 136 m²/g and crystal sizes of 1.6 microns. SEM results showed crystal structures that were regular and pyramidal in shape. This catalyst only showed anatase phase. This favoured phase could be due to iron ions inserted into the TiO2 lattice and forming Ti-O-Fe bonds. It was found that doping TiO2 with 5 wt. % Fe caused a red shift in the absorption of the material to the visible light range and there was an increased absorption in the ultraviolet-visible diffuse reflectance spectroscopy, in the 450-590 nm range. These characteristics are very favourable for the use of 'free' visible light in order to activate the Fe (5 wt. %) doped TiO2 photocatalyst. [Received: September 4, 2009; Accepted: November 30, 2009

Maria D. Salazar-Villalpando; Anthony Cugini; Adam C. Miller

2010-01-01T23:59:59.000Z

312

Ca2+-Doped CeBr3 Scintillating Materials  

SciTech Connect (OSTI)

Despite the outstanding scintillation performance characteristics of cerium tribromide (CeBr3) and cerium-activated lanthanum tribromide, their commercial availability and application are limited due to the difficulties of growing large, crack-free single crystals from these fragile materials. This investigation employed aliovalent doping to increase crystal strength while maintaining the optical properties of the crystal. One divalent dopant (Ca2+) was used as a dopant to strengthen CeBr3 without negatively impacting scintillation performance. Ingots containing nominal concentrations of 1.9% of the Ca2+ dopant were grown. Preliminary scintillation measurements are presented for this aliovalently doped scintillator. Ca2+-doped CeBr3 exhibited little or no change in the peak fluorescence emission for 371 nm optical excitation for CeBr3. The structural, electronic, and optical properties of CeBr3 crystals were studied using the density functional theory within the generalized gradient approximation. The calculated lattice parameters are in good agreement with the experimental data. The energy band structures and density of states were obtained. The optical properties of CeBr3, including the dielectric function, were calculated.

Guss, Paul [NSTec; Foster, Michael E. [SNL; Wong, Bryan M. [SNL; Doty, F. Patrick [SNL; Shah, Kanai [RMD; Squillante, Michael R. [RMD; Shirwadkar, Urmila [RMD; Hawrami, Rastgo [RMD; Tower, Josh [RMD; Yuan, Ding [NSTec

2014-01-01T23:59:59.000Z

313

Supercontinuum generation and lasing in thulium doped tellurite microstructured fibers  

SciTech Connect (OSTI)

We report supercontinuum (SC) generation in Tm{sup 3+} doped tellurite microstructured fibers (TMFs) pumped by a 1.56??m femtosecond fiber laser. In comparison with SC generation in undoped TMFs, the SC spectral bandwidth and the spectral intensity in the wavelength region of >1.9??m are evidently enlarged in Tm{sup 3+} doped TMFs owing to the contribution of the combination of linear gain of Tm{sup 3+} and the nonlinear optical effects to spectral broadening. Furthermore, a transition from SC generation to 1.887??m lasing (Tm{sup 3+}: {sup 3}F{sub 4}?{sup 3}H{sub 6} transition) is observed in Tm{sup 3+} doped TMFs by varying the pulse width of the pump laser from 0.29 to 3.47 ps, which gives the evidence of the above spectral broadening mechanism. This is the first observation of the transition from SC generation to lasing, to the best of our knowledge.

Jia, Zhi-Xu; Liu, Lai; Yao, Chuan-Fei; Qin, Guan-Shi, E-mail: qings@jlu.edu.cn; Qin, Wei-Ping, E-mail: wpqin@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Ohishi, Yasutake [Research Center for Advanced Photon Technology, Toyota Technological Institute, 2-12-1 Hisakata, Tempaku, Nagoya 468-8511 (Japan)

2014-02-14T23:59:59.000Z

314

Doping of germanium and silicon crystals with non-hydrogenic acceptors for far infrared lasers  

DOE Patents [OSTI]

A method for doping semiconductors used for far infrared lasers with non-hydrogenic acceptors having binding energies larger than the energy of the laser photons. Doping of germanium or silicon crystals with beryllium, zinc or copper. A far infrared laser comprising germanium crystals doped with double or triple acceptor dopants permitting the doped laser to be tuned continuously from 1 to 4 terahertz and to operate in continuous mode. A method for operating semiconductor hole population inversion lasers with a closed cycle refrigerator.

Haller, Eugene E. (Berkeley, CA); Brundermann, Erik (Berlin, DE)

2000-01-01T23:59:59.000Z

315

E-Print Network 3.0 - anti-doping agency wada Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Collection: Engineering 10 Trans-Tasman Law and Legal Practice Conference August 2010 Summary: Legislation David Howman, Director-General, World Anti-Doping Agency, Montreal,...

316

Ho3+-doped nanophase glass ceramics for efficiency enhancement in silicon solar cells  

Science Journals Connector (OSTI)

Currently Er3+-doped fluorides are being used as upconversion phosphors to enhance the efficiency of Si solar cells, to our knowledge. However, this enhancement is...

Lahoz, Fernando

2008-01-01T23:59:59.000Z

317

One-pot synthesis of highly mesoporous antimony-doped tin oxide...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

One-pot synthesis of highly mesoporous antimony-doped tin oxide from interpenetrating inorganicorganic networks Authors: Volosin, A.M., Sharma, S., Traverse, C., Newman, N., and...

318

E-Print Network 3.0 - anti-doping agency criteria Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Engineering, McGill University Collection: Engineering 3 White Paper: Center for ETHICS* College of Education Summary: Anti-Doping Agency United States Marine Corps,...

319

Effect of alkali-metal doping on photoluminescence of CdS films  

Science Journals Connector (OSTI)

It is established that doping of CdS polycrystalline films with alkaline metals (Li,... Cd 2? ...cation vacancies, which are nonradiative recombination centers ...

V. G. Klyuev; T. L. Maiorova

2007-05-01T23:59:59.000Z

320

SU-8 doped and encapsulated n-type graphene nanomesh with high air stability  

SciTech Connect (OSTI)

N-type doping of graphene with long-term chemical stability in air represents a significant challenge for practical application of graphene electronics. This paper reports a reversible doping method to achieve highly stable n-type graphene nanomeshes, in which the SU-8 photoresist simultaneously serves as an effective electron dopant and an excellent encapsulating layer. The chemically stable n-type characteristics of the SU-8 doped graphene were evaluated in air using their Raman spectra, electrical transport properties, and electronic band structures. The SU-8 doping does minimum damage to the hexagonal carbon lattice of graphene and is completely reversible by removing the uncrosslinked SU-8 resist.

Al-Mumen, Haider [Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824 (United States) [Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Electrical Engineering, University of Babylon, Babylon (Iraq); Dong, Lixin; Li, Wen, E-mail: wenli@egr.msu.edu [Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824 (United States)] [Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824 (United States)

2013-12-02T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Enhanced broadband excited upconversion luminescence in Ho-doped glasses by codoping with bismuth  

Science Journals Connector (OSTI)

We report enhanced green and red upconversion (UC) luminescence in Ho3+-doped oxyfluoride germanate glass by introducing bismuth near-infrared active centers as sensitizers....

Xu, Beibei; Bai, Gongxun; Wang, Juechen; Guo, Qiangbing; Tan, Dezhi; Chen, Weibo; Liu, Xiaofeng; Zhou, Shifeng; Hao, Jianhua; Qiu, Jianrong

2014-01-01T23:59:59.000Z

322

E-Print Network 3.0 - apical oxygen doping Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Collection: Materials Science ; Chemistry 45 Theoretical search for spintronic and electrochromic device materials based on Li-intercalated transition-metal-doped anatase TiO2...

323

E-Print Network 3.0 - amorphous semiconductors doped Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Centre de mathmatiques Collection: Mathematics 69 Synthesis Of Nitrogen-Doped Graphene Films For Lithium Battery Application Summary: of amorphous carbon along with...

324

Bismuth-doped optical fibres: A new breakthrough in near-IR lasing media  

SciTech Connect (OSTI)

Recent results demonstrate that bismuth-doped optical fibres have considerable potential as near-IR active lasing media. This paper examines bismuth-doped fibres intended for the fabrication of fibre lasers and optical amplifiers and reviews recent results on the luminescence properties of various types of bismuth-doped fibres and the performance of bismuth-doped fibre lasers and optical amplifiers for the spectral range 1150 - 1550 nm. Problems are discussed that have yet to be solved in order to improve the efficiency of the bismuth lasers and optical amplifiers. (optical fibres, lasers and amplifiers. properties and applications)

Dianov, Evgenii M [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation)

2012-09-30T23:59:59.000Z

325

Thermal-induced nonlinear optical characteristics of ethanol solution doped with silver nanoparticles  

Science Journals Connector (OSTI)

The investigation of nonlinear optical characteristics of ethanol solution doped with silver nanoparticles is presented. A large thermal-induced third-order nonlinear refractive...

Mao, Zhengle; Qiao, Lingling; He, Fei; Liao, Yang; Wang, Chen; Cheng, Ya

2009-01-01T23:59:59.000Z

326

Characterization of chemical bath deposited CdS thin films doped with methylene blue and Er3+  

Science Journals Connector (OSTI)

The optical, electrical, and structural properties of CdS thin films grown by chemical bath deposition and simultaneously doped with methylene blue (MB) and Er3+ were studied. Doping was achieved by adding a c...

S. A. Tomás; R. Lozada-Morales; O. Portillo…

2008-01-01T23:59:59.000Z

327

Efficient Mn-doped CdS quantum dot sensitized solar cells based on SnO2 microsphere photoelectrodes  

Science Journals Connector (OSTI)

Mn-doped CdS quantum dot sensitized solar cells based on...2...microsphere photoelectrodes are prepared with successive ionic layer adsorption and reaction method. It is found that with Mn-doped CdS quantum dot s...

Lu Liu; Miaoliang Huang; Zhang Lan…

2014-02-01T23:59:59.000Z

328

CdS nanoparticles in porous silicate glasses: energy characteristics, photocatalytic activity, and the effect of silver ion doping  

Science Journals Connector (OSTI)

Energy diagrams were constructed for CdS nanoparticles doped with silver ions and incorporated into silicate...

A. I. Kryukov; N. P. Smirnova; A. V. Korzhak…

329

Nitrogen-Doped Mesoporous Carbon for Carbon Capture – A Molecular Simulation Study  

Science Journals Connector (OSTI)

Using molecular simulation, we investigate the effect of nitrogen doping on adsorption capacity and selectivity of CO2 versus N2 in model mesoporous carbon. We show that nitrogen doping greatly enhances CO2 adsorption capacity; with a 7 wt % dopant ...

Ravichandar Babarao; Sheng Dai; De-en Jiang

2012-02-29T23:59:59.000Z

330

Magnetically Mediated Transparent Conductors: In2O3 Doped with Mo J. E. Medvedeva*  

E-Print Network [OSTI]

Magnetically Mediated Transparent Conductors: In2O3 Doped with Mo J. E. Medvedeva* Department August 2006) First-principles band structure investigations of the electronic, optical, and magnetic properties of Mo- doped In2O3 reveal the vital role of magnetic interactions in determining both

Medvedeva, Julia E.

331

Indium and tellurium doping of CdS crystals in cadmium vapor and their luminescent properties  

Science Journals Connector (OSTI)

A technique is devised for vapor-phase doping of CdS in the quaternary system Cd-In-Te-S. CdS crystals are doped with In and Te via four-zone ... InTe vapors. The luminescence spectra of the CdS?In,Te?[Cd] crysta...

I. N. Odin; M. V. Chukichev; M. E. Rubina

332

Chemical bath deposition of CdS thin films doped with Zn and Cu  

Science Journals Connector (OSTI)

Zn- and Cu-doped CdS thin films were deposited onto glass substrates...2 and CuCl2...were incorporated as dopant agents into the conventional CdS chemical bath in order to promote the CdS doping process. The effe...

A I OLIVA; J E CORONA; R PATIÑO; A I OLIVA-AVILÉS

2014-04-01T23:59:59.000Z

333

Indium and tellurium doping of CdS crystals in cadmium vapor and their luminescent properties  

Science Journals Connector (OSTI)

—A technique is devised for vapor-phase doping of CdS in the quaternary system Cd—In—Te—S. CdS crystals are doped with In and Te via four-zone ... InTe vapors. The luminescence spectra of the CdS?In,Te?[Cd] cryst...

I. N. Odin; M. V. Chukichev; M. E. Rubina

334

Spectroscopic studies on Zn-doped CdS nanopowders prepared by simple coprecipitation method  

Science Journals Connector (OSTI)

A series of Zn-doped cadmium sulfide (CdS:Zn) nanopowders were prepared by a simple ... nanosize and cubic structure at room temperature. Doping with Zn in CdS does not lead to any structural phase ... the lattic...

H. Sekhar; D. Narayana Rao

2012-02-01T23:59:59.000Z

335

Luminescent Properties of CdS Crystals Doped with Gallium and Tellurium in Cadmium Vapor  

Science Journals Connector (OSTI)

A technique is devised for vapor-phase doping CdS in the quaternary system Cd–Ga–Te–S. CdS crystals are doped with Ga and Te via four-zone ... and Cd (the more volatile component of CdS). The luminescence spectra...

I. N. Odin; M. V. Chukichev; M. E. Rubina

2003-07-01T23:59:59.000Z

336

Structural and magnetic characterization of norbornenedeuterated norbornene dicarboxylic acid diblock copolymers doped with iron oxide  

E-Print Network [OSTI]

, Ag, Pd, Pt, Cu) [5­9] and semiconductor nanoclusters (PbS, CdS, ZnS) [10­12] were synthesized within diblock copolymers doped with iron oxide nanoparticles Pinar Akcoraa , Xin Zhangb , Bindhu Varughesec 2005 Available online 29 April 2005 Abstract A series of iron oxide doped norbornene (NOR

Rubloff, Gary W.

337

Luminescence and Electrical Properties of CdS Films Doped with Potassium and Sodium  

Science Journals Connector (OSTI)

CdS films, both pure and doped with the alkali metals Na and K, ... -power UV radiation have been obtained. The doping of samples results in a tenfold increase ... nm) as compared to pure samples of CdS. Upon irr...

V. G. Klyuev; T. L. Maiorova; A. V. Naumov…

338

Quantum confinement effects in Gd-doped CdS nanoparticles prepared by chemical precipitation technique  

Science Journals Connector (OSTI)

CdS and Gd-doped CdS nanoparticles have been synthesized by chemical precipitation ... The X-ray diffraction patterns show that the CdS and Gd-doped CdS nanoparticles exhibit hexagonal structure. The high resolu...

M. Thambidurai; N. Muthukumarasamy…

2013-11-01T23:59:59.000Z

339

Re-dispersible Li+ and Eu3+ co-doped CdS nanoparticles: Luminescence studies  

Science Journals Connector (OSTI)

Re-dispersible CdS, 5 at.% Eu3+-doped CdS, 2 at.% Li+ and 5 at.% Eu3+ co-doped CdS nanoparticles in organic solvent are prepared by ... at a low temperature of 170°C. CdS nanoparticles have spherical shape with a...

N. S. Gajbhiye; Raghumani Singh Ningthoujam; Asar Ahmed; D. K. Panda…

2008-02-01T23:59:59.000Z

340

Magnetic and structural characterization of transition metal co-doped CdS nanoparticles  

Science Journals Connector (OSTI)

We report the structural and magnetic properties of the CdS nanoparticles co-doped with Ni and Cu; 3% Ni, Cu co-doped CdS nanoparticles were synthesized by using wet chemical ... average diameter of the Ni, Cu co...

Sanjeev Kumar; Sunil Kumar; Sanyog Jain; N. K. Verma

2012-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Raman characterization of boron-doped multiwalled carbon nanotubes J. Maultzsch,a)  

E-Print Network [OSTI]

. We interpret this result as an indication that the high-energy mode in carbon nanotubes is defectRaman characterization of boron-doped multiwalled carbon nanotubes J. Maultzsch,a) S. Reich, and C of boron-doped multiwalled carbon nanotubes. The Raman intensities are analyzed as a function

Nabben, Reinhard

342

Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped Emmanuel Rousseau  

E-Print Network [OSTI]

Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped silicon the role of surface plasmons for nanoscale radiative heat transfer between doped silicon surfaces. We derive a new accurate and closed-form expression of the radiative near- field heat transfer. We also

Paris-Sud XI, Université de

343

Stability of Graphene doping with MoO_3 and I_2  

E-Print Network [OSTI]

We dope graphene by evaporation of MoO_3 or by solution-deposition of I_2 and assess the doping stability for its use as transparent electrodes. Electrical measurements show that both dopants increase the graphene sheet conductivity and find that Mo...

D’Arsié, Lorenzo; Esconjauregui, Santiago; Weatherup, Robert; Guo, Yuzheng; Bhardwaj, Sunil; Centeno, Alba; Zurutuza, Amaia; Cepek, Cinzia; Robertson, John

2014-09-08T23:59:59.000Z

344

Chemical Expansion and Frozen-in Oxygen Vacancies in Pr-doped Ceria , S. R. Bishopa  

E-Print Network [OSTI]

, USA Doped CeO2 is a promising candidate for solid oxide fuel cell electrolyte and electrode-7). Acceptor doped ceria is regarded as a promising candidate for several applications as solid oxide fuel cell temperatures and reduction/oxidation behavior. In the fuel cell application, CeO2-based solid electrolytes

Yildiz, Bilge

345

Joining of highly aluminum-doped lanthanum strontium manganese oxide with tetragonal zirconia by plastic deformation  

E-Print Network [OSTI]

Joining of highly aluminum-doped lanthanum strontium manganese oxide with tetragonal zirconia February 2008; accepted 24 March 2008 Abstract Aluminum-doped lanthanum strontium manganese oxide, La0.77Sr at the interface. © 2008 Elsevier B.V. All rights reserved. Keywords: Lanthanum strontium aluminum manganese oxide

Dutta, Prabir K.

346

Tuning carrier type and density in Bi2Se3 by Ca-doping  

E-Print Network [OSTI]

samples. Two x = 0.012 Ca-doped samples have the smallest?p-type? and lower ?n-type? Ca doping have a larger E 0 .This indicates that x = 0.012 Ca is close to the compensate

2010-01-01T23:59:59.000Z

347

High-performace cladding-pumped erbium-doped fibre laser and amplifier  

SciTech Connect (OSTI)

We report cladding-pumped erbium-doped fibre laser and amplifier configurations. Through fibre design optimisation, we have achieved a record-high laser slope efficiency, 40 % with respect to absorbed pump power ({lambda} = 976 nm), and an output power of 7.5 W. The erbium-doped fibre amplifier efficiency reaches 32 %.

Kotov, L V; Likhachev, M E; Bubnov, M M; Medvedkov, O I; Lipatov, D S; Vechkanov, N N; Guryanov, Aleksei N

2012-05-31T23:59:59.000Z

348

In situ doping control of the surface of high-temperature superconductors  

E-Print Network [OSTI]

LETTERS In situ doping control of the surface of high-temperature superconductors M. A. HOSSAIN1 to systematic studies of high- temperature superconductors, such as creating new electron- doped superconductors.1038/nphys998 Central to the understanding of high-temperature superconductivity is the evolution

Michelson, David G.

349

Electrical properties of Er-doped In0.53Ga0.47As  

E-Print Network [OSTI]

03C117-3 Burke et al. : Electrical properties of Er-doped InElectrical properties of Er-doped In 0.53 Ga 0.47 As PeterBahk and John E. Bowers Electrical and Computer Engineering

Burke, Peter G.; Lu, Hong; Rudawski, Nicholas G.; Gossard, Arthur G.; Bahk, Je-Hyeong; Bowers, John E.

2011-01-01T23:59:59.000Z

350

Tunable White-Light-Emitting Mn-Doped ZnSe Nanocrystals Vijay Kumar Sharma,  

E-Print Network [OSTI]

Tunable White-Light-Emitting Mn-Doped ZnSe Nanocrystals Vijay Kumar Sharma, Burak Guzelturk, Talha report white-light-emitting Mn-doped ZnSe nanocrystals (NCs) that are synthesized using modified orange emission (580 nm), allowed us to achieve excitation wavelength tailorable white-light generation

Demir, Hilmi Volkan

351

Hydrogen adsorption on Graphene and Nitrogen Doped Graphene Monolayers: A First Principles Study  

E-Print Network [OSTI]

Hydrogen adsorption on Graphene and Nitrogen Doped Graphene Monolayers: A First Principles Study Abstract This study examines the properties of graphene and nitrogen doped graphene by way of first principles spin-polarized Density Functional Theory calculations. Why graphene is so unique comes from

Petta, Jason

352

Nitrogen-doped graphene and its electrochemical applications Yuyan Shao,a  

E-Print Network [OSTI]

Nitrogen-doped graphene and its electrochemical applications Yuyan Shao,a Sheng Zhang,a Mark Hst March 2010, Accepted 4th June 2010 DOI: 10.1039/c0jm00782j Nitrogen-doped graphene (N-graphene) is obtained by exposing graphene to nitrogen plasma. N-graphene exhibits much higher electrocatalytic activity

Aksay, Ilhan A.

353

VISIBLE AND INFRARED RARE-EARTH ACTIVATED ELECTROLUMINESCENCE FROM ERBIUM DOPED GaN  

E-Print Network [OSTI]

. At the same time novel work is being conducted using rare earth elements as sources of light emission. Results. III-V semiconductors doped with rare-earth elements have also been used10VISIBLE AND INFRARED RARE-EARTH ACTIVATED ELECTROLUMINESCENCE FROM ERBIUM DOPED GaN M. Garter*, R

Steckl, Andrew J.

354

The Electric and Optical Properties of Doped Small Molecular Organic Light-Emitting Devices  

SciTech Connect (OSTI)

Organic light-emitting devices (OLEDs) constitute a new and exciting emissive display technology. In general, the basic OLED structure consists of a stack of fluorescent organic layers sandwiched between a transparent conducting-anode and metallic cathode. When an appropriate bias is applied to the device, holes are injected from the anode and electrons from the cathode; some of the recombination events between the holes and electrons result in electroluminescence (EL). Until now, most of the efforts in developing OLEDs have focused on display applications, hence on devices within the visible range. However some organic devices have been developed for ultraviolet or infrared emission. Various aspects of the device physics of doped small molecular OLEDs were described and discussed. The doping layer thickness and concentration were varied systematically to study their effects on device performances, energy transfer, and turn-off dynamics. Low-energy-gap DCM2 guest molecules, in either {alpha}-NPD or DPVBi host layers, are optically efficient fluorophores but also generate deep carrier trap-sites. Since their traps reduce the carrier mobility, the current density decreases with increased doping concentration. At the same time, due to efficient energy transfer, the quantum efficiency of the devices is improved by light doping or thin doping thickness, in comparison with the undoped neat devices. However, heavy doping induces concentration quenching effects. Thus, the doping concentration and doping thickness may be optimized for best performance.

Kwang-Ohk Cheon

2003-08-05T23:59:59.000Z

355

Effect of Microstructure of Nitrogen-Doped Graphene on Oxygen Reduction Activity in Fuel Cells  

Science Journals Connector (OSTI)

Effect of Microstructure of Nitrogen-Doped Graphene on Oxygen Reduction Activity in Fuel Cells ... The optimized structures for OOH, OOH+ or O2 adsorption (ads) to graphene were obtained through structural optimization calculations. ... Thus, to optimize the catalytic performance, materials structures should be controlled to have small N doping clusters in combination with material defects. ...

Lipeng Zhang; Jianbing Niu; Liming Dai; Zhenhai Xia

2012-04-10T23:59:59.000Z

356

Nitrogen-Doped Fullerene as a Potential Catalyst for Hydrogen Fuel Cells  

Science Journals Connector (OSTI)

Nitrogen-Doped Fullerene as a Potential Catalyst for Hydrogen Fuel Cells ... We examine the possibility of nitrogen-doped C60 fullerene (N-C60) as a cathode catalyst for hydrogen fuel cells. ... N-C60 fullerene is a potential cathode catalyst for hydrogen fuel cells. ...

Feng Gao; Guang-Lin Zhao; Shizhong Yang; James J. Spivey

2012-09-19T23:59:59.000Z

357

Intersubband absorption in boron-doped multiple Ge quantum dots J. L. Liu,a)  

E-Print Network [OSTI]

Intersubband absorption in boron-doped multiple Ge quantum dots J. L. Liu,a) W. G. Wu, A. Balandin; accepted for publication 3 November 1998 The intersubband absorption in self-assembled boron-doped multiple and undoped Si barriers. The infrared absorption as a function of wavelength is measured by Fourier transform

358

Erbium-doped transparent glass ceramic optical Characterization using mass spectroscopy and molecular dynamics modeling.  

E-Print Network [OSTI]

Erbium-doped transparent glass ceramic optical fibres: Characterization using mass spectroscopy) doped silica-based optical fibres with transparent glass ceramic (TGC) core were fabricated through properties of the erbium ions embedded within the phospho-silicate DNP. These results permit to get more

Boyer, Edmond

359

Generation of high peak power pulse using 2 stage erbium-doped fiber amplifier  

E-Print Network [OSTI]

-doped fiber. For the second stage, two 1480nm pump lasers were used to pump erbium-doped fiber in both forward and backward propagating direction. The signal laser was modulated to produce pulses with high repetition rate high peak power. The first stage...

Lee, Kyung-Woo

2012-06-07T23:59:59.000Z

360

Bose Glass of Quasiparticles in Doped Quantum Magnet Gregory S. Boebinger, National High Magnetic Field Laboratory  

E-Print Network [OSTI]

Bose Glass of Quasiparticles in Doped Quantum Magnet Gregory S. Boebinger, National High Magnetic. This BEC can localize in the presence of disorder caused by Br- doping to form a Bose Glass. The BEC-Bose Glass (BEC-BG) transition can be carefully controlled by magnetic field, allowing us to sensitively

Weston, Ken

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Electrical noise characteristics of a doped silicon microcantilever heater-thermometer  

E-Print Network [OSTI]

Electrical noise characteristics of a doped silicon microcantilever heater-thermometer Elise A with resistive heater-thermometers,10­13 there is a lack of published reports on the electrical noise silicon heater- thermometer cantilevers.12 However, a key difference is that doped silicon heater-thermometers

King, William P.

362

Characterization of gallium-doped CdS thin films grown by chemical bath Hani Khallaf a  

E-Print Network [OSTI]

Characterization of gallium-doped CdS thin films grown by chemical bath deposition Hani Khallaf In-situ doping with group III elements has been widely used to decrease the dark resistivity of CdS technique for aluminum in-situ doping of CdS. We have also shown that due to extremely low solubility

Chow, Lee

363

Co-sputtered Aluminum Doped Zinc Oxide Thin Film as Transparent Anode for Organic Light-emitting Diodes  

E-Print Network [OSTI]

Co-sputtered Aluminum Doped Zinc Oxide Thin Film as Transparent Anode for Organic Light and Technology, Clear Water Bay, Kowloon, Hong Kong, China ABSTRACT Aluminum doped zinc oxide (AZO that MTDATA matches better with AZO than CuPc, which served as hole injection layer. Keywords: Aluminum doped

364

Correlation of defect centers with second-harmonic generation in Ge-doped and Ge–P-doped silica-core single-mode fibers  

Science Journals Connector (OSTI)

The origin of frequency doubling in Ge-doped silica-core single-mode glass fibers has been investigated with electron-spin-resonance spectrometry. Correlations have been observed...

Tsai, T E; Saifi, M A; Friebele, E J; Österberg, U; Griscom, D L

1989-01-01T23:59:59.000Z

365

Molecular dynamics investigations of boron doping in a-Si:H  

SciTech Connect (OSTI)

The rather low doping efficiency of B in a-Si:H is almost always explained by the argument that almost all of the B is incorporated into three-fold coordinated sites and that B is inert or non-doping in this configuration. Using ab initio molecular dynamics, the authors have studied the energetics and doping (electronic structure) consequences of B incorporation into a-Si:H both with and without H passivation. Their results suggest that the conventional view is in error and that the low doping efficiency is primarily due to H passivation. These results are consistent with the low doping efficiency of B as well as NMR studies on the large electric field gradients experienced by the B atoms and on NMR double resonance studies of B-H neighboring distances.

Fedders, P.A.; Drabold, D.A.

1997-07-01T23:59:59.000Z

366

Quantitative determination of local potential values in inhomogeneously doped semiconductors by scanning tunneling microscopy  

Science Journals Connector (OSTI)

Local potential changes arising from nanoscale three-dimensional spatial fluctuations in the dopant distribution in Zn-doped GaAs were investigated quantitatively by scanning tunneling microscopy and spectroscopy at (110) cleavage surfaces. Tunneling spectra measured in areas with different local doping concentration show apparent shifts of the valence band edge and apparent changes of the band gap. A quantitative analysis, combined with band bending and tunnel current simulations, demonstrates that these effects arise from tip-induced band bending that modulates the real potential changes. It is illustrated how exact potential changes between locally high and low doped areas can be determined. It is found that the local potential fluctuations in three-dimensionally doped semiconductors are approximately one order of magnitude smaller that those observed in two-dimensionally doped semiconductors.

P. H. Weidlich, R. E. Dunin-Borkowski, and Ph. Ebert

2011-08-29T23:59:59.000Z

367

Spin-dependent electron transport in zinc- and manganese-doped adenine molecules  

SciTech Connect (OSTI)

The spin-dependent electron transport properties of zinc- and manganese-doped adenine molecules connected to zigzag graphene leads are studied in the zero bias regime using the non-equilibrium Green's function method. The conductance of the adenine molecule increased and became spin-dependent when a zinc or manganese atom was doped into the molecules. The effects of a transverse electric field on the spin-polarization of the transmitted electrons were investigated and the spin-polarization was controlled by changing the transverse electric field. Under the presence of a transverse electric field, both the zinc- and manganese-doped adenine molecules acted as spin-filters. The maximum spin-polarization of the manganese-doped adenine molecule was greater than the molecule doped with zinc.

Simchi, Hamidreza, E-mail: simchi@iust.ac.ir [Department of Physics, Iran University of Science and Technology, Narmak, Tehran 16844 (Iran, Islamic Republic of); Semiconductor Technology Center, Tehran 16844 (Iran, Islamic Republic of); Esmaeilzadeh, Mahdi, E-mail: mahdi@iust.ac.ir; Mazidabadi, Hossein [Department of Physics, Iran University of Science and Technology, Narmak, Tehran 16844 (Iran, Islamic Republic of)

2014-01-28T23:59:59.000Z

368

Atmospheric Oxygen Binding and Hole Doping in Deformed Graphene on a SiO2 Substrate  

E-Print Network [OSTI]

Using micro-Raman spectroscopy and scanning tunneling microscopy, we study the relationship between structural distortion and electrical hole doping of graphene on a silicon dioxide substrate. The observed upshift of the Raman G band represents charge doping and not compressive strain. Two independent factors control the doping: (1) the degree of graphene coupling to the substrate, and (2) exposure to oxygen and moisture. Thermal annealing induces a pronounced structural distortion due to close coupling to SiO2 and activates the ability of diatomic oxygen to accept charge from graphene. Gas flow experiments show that dry oxygen reversibly dopes graphene; doping becomes stronger and more irreversible in the presence of moisture and over long periods of time. We propose that oxygen molecular anions are stabilized by water solvation and electrostatic binding to the silicon dioxide surface.

Sunmin Ryu; Li Liu; Stephane Berciaud; Young-Jun Yu; Haitao Liu; Philip Kim; George W. Flynn; Louis E. Brus

2010-11-13T23:59:59.000Z

369

Devitfrification Properties Of Bismuth Borate Glasses Doped With Trivalent Ions  

SciTech Connect (OSTI)

Bismuth borate glasses and crystalline phases have outstanding luminescent and nonlinear optical properties; therefore there is lot of interest in their preparation and characterization. In this study we report the crystallization properties of bismuth borate glasses doped with trivalent ions. Glasses of the composition: xBi{sub 2}O{sub 3}-(100-x)B{sub 2}O{sub 3} (x = 20, 25, 30, 37.5, 40, 50, 60 and 66 mol %) and 40Bi{sub 2}O{sub 3}-1Tv{sub 2}O{sub 3}-59B{sub 2}O{sub 3}(where Tv = Al, Nd and Eu) were prepared by melt quench technique and devitrified by heat treatment above their glass transition temperatures for several hours. The crystalline phases produced were characterized by FTIR absorption spectroscopy, DTA and X-ray diffraction. Bi{sub 3}B{sub 5}O{sub 12} was found to be the predominant phase in all crystallized samples containing Bi{sub 2}O{sub 3} concentration of {<=}40 mol %, at higher Bi{sub 2}O{sub 3} concentration, we observed the formation of Bi{sub 4}B{sub 2}O{sub 9} phase. Glasses with Bi{sub 2}O{sub 3} concentration of {<=}37.5 mol % produced Bi{sub 2}B{sub 8}O{sub 15} phase on crystallization. The metastable BiBO{sub 3}-I phase was formed by short duration heat treatment (less than 5 hours) of the initial glass sample. Doping with rare earth ions like Eu{sup 3+} and Nd{sup 3+} promotes the formation of BiBO{sub 3}-II phase while Al{sup 3+} doping suppresses it.

Khanna, Atul [Department of Physics, Guru Nanak Dev University, Amritsar-143005, Punjab (India); Bajaj, Anu [Department of Applied Sciences, Adesh Institute of Engineering and Technology, Faridkot-151203, Punjab (India)

2010-12-01T23:59:59.000Z

370

Unusual dielectric response in cobalt doped reduced graphene oxide  

SciTech Connect (OSTI)

Intensive research on cobalt doped reduced graphene oxide (Co-RGO) to investigate the modification in graphene magnetism and spin polarization due to presence of transition metal atom has been carried out, however, its dielectric spectroscopy, particularly, how capacitance changes with impurity levels in graphene is relatively unexplored. In the present work, dielectric spectroscopy along with magneto-dielectric effect are investigated in Co-RGO. Contrary to other materials, here permittivity increases abruptly with frequency in the low frequency region and continues to increase till 10{sup 7}?Hz. This unusual behavior is explained on the basis of trap induced capacitance created due to impurity levels.

Akhtar, Abu Jahid; Gupta, Abhisek; Kumar Shaw, Bikash; Saha, Shyamal K., E-mail: cnssks@iacs.res.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India)

2013-12-09T23:59:59.000Z

371

Nitrogen-doped Graphene and Its Electrochemical Applications  

SciTech Connect (OSTI)

Nitrogen-doped graphene (N-graphene) is obtained by exposing graphene to nitrogen plasma. N-graphene exhibits much higher electrocatalytic activity toward oxygen reduction and H2O2 reduction than graphene, and much higher durability and selectivity than the widely-used expensive Pt. The excellent electrochemical performance of N-graphene is attributed to nitrogen functional groups and the specific properties of graphene. This indicates that N-graphene is promising for applications in electrochemical energy devices (fuel cells, metal-air batteries) and biosensors.

Shao, Yuyan; Zhang, Sheng; Engelhard, Mark H.; Li, Guosheng; Shao, Guocheng; Wang, Yong; Liu, Jun; Aksay, Ilhan A.; Lin, Yuehe

2010-06-04T23:59:59.000Z

372

Zero-Reabsorption Doped-Nanocrystal Luminescent Solar Concentrators  

Science Journals Connector (OSTI)

Optical concentration can lower the cost of solar energy conversion by reducing photovoltaic cell area and increasing photovoltaic efficiency. ... (31) Depending on the semiconductor, they can be made from low cost, nontoxic, Earth-abundant starting materials, and they are compatible with a variety of economical solution-based synthesis and processing techniques advantageous for integration into polymer or glass waveguides. ... These nanocrystals are unique among colloidal doped semiconductor nanocrystals reported to date in that quantum confinement allows tuning of the CdSe bandgap energy across the Mn2+ excited-state energies. ...

Christian S. Erickson; Liam R. Bradshaw; Stephen McDowall; John D. Gilbertson; Daniel R. Gamelin; David L. Patrick

2014-03-12T23:59:59.000Z

373

Fabrication of solar cells with counter doping prevention  

DOE Patents [OSTI]

A solar cell fabrication process includes printing of dopant sources over a polysilicon layer over backside of a solar cell substrate. The dopant sources are cured to diffuse dopants from the dopant sources into the polysilicon layer to form diffusion regions, and to crosslink the dopant sources to make them resistant to a subsequently performed texturing process. To prevent counter doping, dopants from one of the dopant sources are prevented from outgassing and diffusing into the other dopant source. For example, phosphorus from an N-type dopant source is prevented from diffusing to a P-type dopant source comprising boron.

Dennis, Timothy D; Li, Bo; Cousins, Peter John

2013-02-19T23:59:59.000Z

374

Origin of the optical gap in half-doped manganites  

Science Journals Connector (OSTI)

We have analyzed the coexisting charge and orbital ordering in half-doped manganites using a model which includes Coulomb and Jahn-Teller orbital polarization interactions. Most surprisingly, the gap in the optical conductivity is reduced by both on-site and intersite Coulomb interactions, but increases and explains the experimental results when the Jahn-Teller terms with orbital polarization are considered. The origin of this behavior is explained within a molecular model which arises in the limit of extreme topological frustration, when single electrons are confined to molecular units consisting of three orbitals.

Mario Cuoco; Canio Noce; Andrzej M. Ole?

2002-09-25T23:59:59.000Z

375

Carrier doping into boron nanobelts by neutron transmutation  

SciTech Connect (OSTI)

We report the effects of a neutron-capture reaction of isotope {sup 10}B on the structure and electrical transport of {sup 10}B-enriched single-crystalline boron nanobelts. Partial amorphization, particularly at the surface of the nanobelt, was observed after thermal neutron irradiation with a dose of 2x10{sup 19} cm{sup -2}. Carrier doping into the nanobelts by neutron transmutation is expected after postannealing. The change in conductance is discussed based on the distribution of localized states in the band gap of {alpha}-tetragonal boron.

Kirihara, Kazuhiro; Shimizu, Yoshiki; Sasaki, Takeshi; Koshizaki, Naoto [Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8565 (Japan); Yamada, Yoichi [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Esaka, Fumitaka [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195 (Japan); Yamamoto, Hiroyuki; Shamoto, Shin-ichi [Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195 (Japan); Kimura, Kaoru [Department of Advanced Materials Science, The University of Tokyo, Kashiwa, Chiba 277-8561 (Japan)

2010-11-22T23:59:59.000Z

376

Controlled Doping of Transition Metal Cations in Alumina Pillared Clays  

Science Journals Connector (OSTI)

First, calcined Al-PILC was dispersed into an aqueous solution of sodium or ammonium ions. ... The ion-doped Al-PILC was then exchanged with an aqueous solution of transition metal salt at a pH of ?4.5 to replace Na+ or NH4+ ions by transition metal cations. ... Analytical techniques such as atomic absorption spectroscopy, X-ray diffraction, diffuse reflectance?ultraviolet?visible spectroscopy, as well as N2 adsorption were used to characterize the PILC products with and without the loading of metal ions. ...

H. Y. Zhu; Z. H. Zhu; G. Q. Lu

2000-05-31T23:59:59.000Z

377

Photochemical doping of graphene oxide with nitrogen for photoluminescence enhancement  

SciTech Connect (OSTI)

Nitrogen-doped graphene oxide (NGO) was synthesized by irradiation of graphene oxide (GO) in NH{sub 3} atmosphere. NGO obtained by irradiation of GO for 10 min has high N content of 13.62 at. %. The photoluminescence (PL) properties of NGO were investigated. The results showed that compared with GO, NGO exhibits significant PL enhancement with a high enhancement ratio of approximately 1501.57%. It may attribute to the high content of amino-like N, which can effectively enhance PL of GO because of the amino conjugation effect.

Liu, Fuchi [Physics Department and Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China) [Physics Department and Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China); College of Physics and Technology, Guangxi Normal University, Guilin 541004 (China); Tang, Nujiang; Tang, Tao; Liu, Yuan; Feng, Qian; Zhong, Wei; Du, Youwei [Physics Department and Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China)] [Physics Department and Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China)

2013-09-16T23:59:59.000Z

378

Photoresponse of Tb{sup 3+} doped phosphosilicate thin films  

SciTech Connect (OSTI)

Phosphosilicate ceramic was doped with Tb{sup 3+} using sol-gel technique to prepare thin films. The films were prepared by spin coating the phosphosilicate sols on SiO{sub x}/indium-tin-oxide/glass substrates. The photocurrent of the films at 355 nm laser excitation was observed. The photoresponse as a function of applied field and laser energy was linear and showed no sign of saturation. The films exhibited very stable photoresponse under a very high number of laser shots.

Lee, B.L.; Cao, Z. [Clemson Univ., SC (United States). Gilbert C. Robinson Dept. of Ceramic and Materials Engineering] [Clemson Univ., SC (United States). Gilbert C. Robinson Dept. of Ceramic and Materials Engineering; Sisk, W.N.; Hudak, J. [Univ. of North Carolina, Charlotte, NC (United States)] [Univ. of North Carolina, Charlotte, NC (United States); Samuels, W.D.; Exarhos, G.J. [Pacific Northwest National Lab., Richland, WA (United States). Materials and Chemical Science] [Pacific Northwest National Lab., Richland, WA (United States). Materials and Chemical Science

1997-09-01T23:59:59.000Z

379

Room temperature ferromagnetism in undoped and Fe doped ZnO nanorods: Microwave-assisted synthesis  

SciTech Connect (OSTI)

One-dimensional (1D) undoped and Fe doped ZnO nanorods of average length {approx}1 {mu}m and diameter {approx}50 nm have been obtained using a microwave-assisted synthesis. The magnetization (M) and coercivity (H{sub c}) value obtained for undoped ZnO nanorods at room temperature is {approx}5x10{sup -3} emu/g and {approx}150 Oe, respectively. The Fe doped ZnO samples show significant changes in M -H loop with increasing doping concentration. Both undoped and Fe doped ZnO nanorods exhibit a Curie transition temperature (T{sub c}) above 390 K. Electron spin resonance and Moessbauer spectra indicate the presence of ferric ions. The origin of ferromagnetism in undoped ZnO nanorods is attributed to localized electron spin moments resulting from surface defects/vacancies, where as in Fe doped samples is explained by F center exchange mechanism. -- Graphical abstract: Room temperature ferromagnetism has been reported in undoped and Fe doped ZnO nanorods of average length {approx}1 {mu}m and diameter {approx}50 nm. Display Omitted Research Highlights: {yields} Microwave-assisted synthesis of undoped and Fe doped ZnO nanorods. {yields} Observation of room temperature ferromagnetism in undoped and Fe doped ZnO nanorods. {yields} Transition temperature (T{sub c}) obtained in undoped and doped samples is above 390 K. {yields} In undoped ZnO origin of ferromagnetism is explained in terms of defects/vacancies. {yields} Ferromagnetism in Fe doped ZnO is explained by F-center exchange mechanism.

Limaye, Mukta V.; Singh, Shashi B. [DST unit on Nanoscience, Department of Physics, University of Pune, Pune 411007 (India); Das, Raja; Poddar, Pankaj [Physical and Materials Chemistry Division, National Chemical Laboratory, Pune 411 008 (India); Kulkarni, Sulabha K., E-mail: s.kulkarni@iiserpune.ac.i [DST unit on Nanoscience, Indian Institute of Science Education and Research, Pune 411021 (India)

2011-02-15T23:59:59.000Z

380

Peak divergence in the curve of magnetoelectric coefficient versus dc bias magnetic field at resonance region for bi-layer magnetostrictive/piezoelectric composites  

SciTech Connect (OSTI)

Magnetoelectric (ME) coefficient dependence on the bias magnetic field at resonance frequencies for the bi-layered bonded Terfenol-D/Pb(Zr,Ti)O{sub 3} composite was investigated. The resonance frequency decreases first and then increases with the bias magnetic field (H{sub DC}), showing a “V” shape in the range of 0 ? 5 kOe. Below the resonance frequency, the pattern of ME coefficient dependence on the H{sub DC} shows a single peak, but splits into a double-peak pattern when the testing frequency increases into a certain region. With increasing the frequency, a divergent evolution of the H{sub DC} patterns was observed. Domain motion and ?E effect combined with magnetostriction-piezoelectric coupling effect were employed to explain this experimental result.

Zuo, Z. J.; Pan, D. A., E-mail: pandean@mater.ustb.edu.cn; Zhang, S. G.; Qiao, L. J. [Institute of Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083 (China)] [Institute of Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083 (China); Jia, Y. M. [Department of Physics, Zhejiang Normal University, Jinhua 321004, Zhejiang Province (China)] [Department of Physics, Zhejiang Normal University, Jinhua 321004, Zhejiang Province (China)

2013-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

High thermal stability and low Gilbert damping constant of CoFeB/MgO bilayer with perpendicular magnetic anisotropy by Al capping and rapid thermal annealing  

SciTech Connect (OSTI)

We demonstrate that the magnetic anisotropy of the CoFeB/MgO bilayer can be manipulated by adding an aluminum capping layer. After rapid thermal annealing, we can achieve large perpendicular magnetic anisotropy of CoFeB with a high thermal stability factor (??=?72) while the Gilbert damping constant can be reduced down to only 0.011 simultaneously. The boron and residual oxygen in the bulk CoFeB layer are properly absorbed by the Al capping layer during annealing, leading to the enhanced exchange stiffness and reduced damping. The interfacial Fe-O bonding can be optimized by tuning annealing temperature and thickness of Al, resulting in enhanced perpendicular anisotropy.

Wang, Ding-Shuo; Lai, Shu-Yu; Lin, Tzu-Ying; Wang, Liang-Wei; Liao, Jung-Wei; Lai, Chih-Huang, E-mail: chlai@mx.nthu.edu.tw [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan (China); Chien, Cheng-Wei; Wang, Yung-Hung [Electronics and Optoelectronics Research Laboratories, Industrial Technology Research Institute, Chutung, Taiwan (China); Ellsworth, David; Lu, Lei; Wu, Mingzhong [Department of Physics, Colorado State University, Fort Collins, Colorado 80523 (United States)

2014-04-07T23:59:59.000Z

382

Crystallization and doping of amorphous silicon on low temperature plastic  

DOE Patents [OSTI]

A method or process of crystallizing and doping amorphous silicon (a-Si) on a low-temperature plastic substrate using a short pulsed high energy source in a selected environment, without heat propagation and build-up in the substrate. The pulsed energy processing of the a-Si in a selected environment, such as BF3 and PF5, will form a doped micro-crystalline or poly-crystalline silicon (pc-Si) region or junction point with improved mobilities, lifetimes and drift and diffusion lengths and with reduced resistivity. The advantage of this method or process is that it provides for high energy materials processing on low cost, low temperature, transparent plastic substrates. Using pulsed laser processing a high (>900.degree. C.), localized processing temperature can be achieved in thin films, with little accompanying temperature rise in the substrate, since substrate temperatures do not exceed 180.degree. C. for more than a few microseconds. This method enables use of plastics incapable of withstanding sustained processing temperatures (higher than 180.degree. C.) but which are much lower cost, have high tolerance to ultraviolet light, have high strength and good transparency, compared to higher temperature plastics such as polyimide.

Kaschmitter, James L. (Pleasanton, CA); Truher, Joel B. (Palo Alto, CA); Weiner, Kurt H. (Campbell, CA); Sigmon, Thomas W. (Beaverton, OR)

1994-01-01T23:59:59.000Z

383

Chloride, bromide and iodide scintillators with europium doping  

DOE Patents [OSTI]

A halide scintillator material is disclosed where the halide may comprise chloride, bromide or iodide. The material is single-crystalline and has a composition of the general formula ABX.sub.3 where A is an alkali, B is an alkali earth and X is a halide which general composition was investigated. In particular, crystals of the formula ACa.sub.1-yEu.sub.yI.sub.3 where A=K, Rb and Cs were formed as well as crystals of the formula CsA.sub.1-yEu.sub.yX.sub.3 (where A=Ca, Sr, Ba, or a combination thereof and X=Cl, Br or I or a combination thereof) with divalent Europium doping where 0.ltoreq.y.ltoreq.1, and more particularly Eu doping has been studied at one to ten mol %. The disclosed scintillator materials are suitable for making scintillation detectors used in applications such as medical imaging and homeland security.

Zhuravleva, Mariya; Yang, Kan

2014-08-26T23:59:59.000Z

384

Properties of boron-doped thin films of polycrystalline silicon  

SciTech Connect (OSTI)

The properties of polycrystalline-silicon films deposited by low pressure chemical vapor deposition and doped heavily in situ boron-doped with concentration level of around 2×10{sup 20}cm{sup ?3} has been studied. Their properties are analyzed using electrical and structural characterization means by four points probe resistivity measurements and X-ray diffraction spectra. The thermal-oxidation process are performed on sub-micron layers of 200nm/c-Si and 200nm/SiO{sub 2} deposited at temperatures T{sub d} ranged between 520°C and 605°C and thermally-oxidized in dry oxygen ambient at 945°C. Compared to the as-grown resistivity with silicon wafers is known to be in the following sequence < and < . The measure X-ray spectra is shown, that the Bragg peaks are marked according to the crystal orientation in the film deposited on bare substrates (poly/c-Si), for the second series of films deposited on bare oxidized substrates (poly/SiO{sub 2}) are clearly different.

Merabet, Souad [Electronic Department, Faculty of Science and Technology, University of Jijel, Cité Ouled-Aissa B. P. 98 Jijel, 18 000 Jijel (Algeria)

2013-12-16T23:59:59.000Z

385

Imaging Local Electronic Corrugations and Doped Regions in Graphene  

SciTech Connect (OSTI)

Electronic structure heterogeneities are ubiquitous in two-dimensional graphene and profoundly impact the transport properties of this material. Here we show the mapping of discrete electronic domains within a single graphene sheet using scanning transmission X-ray microscopy in conjunction with ab initio density functional theory calculations. Scanning transmission X-ray microscopy imaging provides a wealth of detail regarding the extent to which the unoccupied levels of graphene are modified by corrugation, doping and adventitious impurities, as a result of synthesis and processing. Local electronic corrugations, visualized as distortions of the {pi}*cloud, have been imaged alongside inhomogeneously doped regions characterized by distinctive spectral signatures of altered unoccupied density of states. The combination of density functional theory calculations, scanning transmission X-ray microscopy imaging, and in situ near-edge X-ray absorption fine structure spectroscopy experiments also provide resolution of a longstanding debate in the literature regarding the spectral assignments of pre-edge and interlayer states.

B Schultz; C Patridge; V Lee; C Jaye; P Lysaght; C Smith; J Barnett; D Fischer; D Prendergast; S Banerjee

2011-12-31T23:59:59.000Z

386

Electrochemical behavior of reactively sputtered iron-doped nickel oxide  

SciTech Connect (OSTI)

Iron-doped nickel oxide films were deposited by reactive sputtering from elemental and alloy targets in a 20% oxygen/argon atmosphere and were characterized for use as oxygen evolution catalysts. The incorporation of iron reduced the overpotential required for oxygen evolution by as much as 300 mV at a current density of 100 mA/cm{sup 2} compared to undoped nickel oxide deposited under similar conditions. Tafel slopes were reduced from 95 mV/dec in undoped NiO{sub x} films to less than 40 mV/dec for films containing 1.6 to 5.6 mole percent (m/o) iron, indicating a change in the rate-limiting step from the primary discharge of OH{sup {minus}} ions to the recombination of oxygen radicals. Resistivity, structural, and compositional measurements indicate that high oxygen content is necessary to gain the full benefit of the iron dopant. Initial tests in KOH indicate excellent long-term stability. A film deposited from the FeNi alloy target, which exhibited low oxygen overpotentials and a Tafel slope of 35 mV/dec, had not degraded appreciably following more than 7,000 h of operation at an anodic current density of 20 mA/cm{sup 2}. Taken together, the low oxygen evolution reaction overpotentials, the excellent stability in KOH, and the relative insensitivity to iron content indicative that reactively sputtered iron-doped nickel oxide is promising as an oxygen catalyst.

Miller, E.L.; Rocheleau, R.E. [Univ. of Hawaii, Honolulu, HI (United States)

1997-09-01T23:59:59.000Z

387

Silver doped nanobioactive glass particles for bone implant applications  

SciTech Connect (OSTI)

Silica based silver doped nanobioactive glass compositions (58SiO{sub 2}-33CaO-9P{sub 2}O{sub 5} and 58SiO{sub 2}-23CaO-9P{sub 2}O{sub 5}-10Ag{sub 2}O(mol%)) were synthesized by a simple sol-gel route. The prepared samples were comprehensively characterised by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy and scanning electron microscopic studies. The results reveal that the prepared samples have amorphous phase with spherical morphology and having a particle size less than 100 nm. The specific surface areas were 90 and 61 m{sup 2}g{sup -1} respectively. The in vitro bioactivity of glass samples were confirmed by the formation of hydroxyapatite layer on glass surfaces. The Ag{sub 2}O-doped nanobioactive glasse samples shows reveal significant antibacterial activity compare with base glasses.

Prabhu, M.; Kavitha, K.; Karunakaran, G.; Manivasakan, P.; Rajendran, V. [Centre for Nanoscience and Technology, K. S. Rangasamy College of Technology, Tiruchengode - 637215, Namakkal (DT), Tamil Nadu (India)

2013-02-05T23:59:59.000Z

388

Properties of Heavily Doped n?Type Germanium  

Science Journals Connector (OSTI)

The electrical and optical properties of n?type germanium have been studied for doping levels greater than 5×1018 cm?3. Hall coefficient and resistivity measurements show that the electron mobility ? depends upon the specific group V donor used as a dopant and at a given carrier concentration increases in the order ?Aselectrically inactive. Rapid quenching of this material resulted in larger carrier concentrations and a better correlation with crystal growth parameters. Distribution coefficients were calculated from the electrical measurements on antimony?doped crystals grown by a solvent evaporation technique. No significant ``facet effect'' was observed for these crystals. Reflectivity measurements between 2 and 24 ? were used to deduce the electron effective mass as a function of carrier concentration. In the carrier concentration range studied (up to 8×1019 cm?3) the effective mass increases only slightly and is independent of the specific dopant. The free carrier absorption is dependent on dopant. The absorption and electrical data are correlated by using elementary conduction theory.

W. G. Spitzer; F. A. Trumbore; R. A. Logan

1961-01-01T23:59:59.000Z

389

Doping-dependent anisotropic superconducting gap in Na1-?(Fe1-xCox)As from London penetration depth  

SciTech Connect (OSTI)

The London penetration depth was measured in single crystals of self-doped Na1-?FeAs (from under doping to optimal doping, Tc from 14 to 27 K) and electron-doped Na(Fe1-xCox)As with x ranging from undoped, x=0, to overdoped, x=0.1. In all samples, the low-temperature variation of the penetration depth exhibits a power-law dependence, ??(T)=ATn, with the exponent that varies in a domelike fashion from n˜1.1 in the underdoped, reaching a maximum of n˜1.9 in the optimally doped, and decreasing again to n˜1.3 on the overdoped side. While the anisotropy of the gap structure follows a universal domelike evolution, the exponent at optimal doping, n˜1.9, is lower than in other charge-doped Fe-based superconductors (FeSCs). The full-temperature range superfluid density, ?s(T)=?(0)/?(T)2, at optimal doping is also distinctly different from other charge-doped FeSCs but is similar to isovalently substituted BaFe2(As1-xPx)2, believed to be a nodal pnictide at optimal doping. These results suggest that the superconducting gap in Na(Fe1-xCox)As is highly anisotropic even at optimal doping.

Cho, Kyuil; Tanatar, Makariy A.; Spyrison, Nicholas; Kim, Hyunsoo; Song, Y.; Dai, Pengcheng; Zhang, C.L.; Prozorov, Ruslan

2012-07-30T23:59:59.000Z

390

Solvothermal synthesis and study of nonlinear optical properties of nanocrystalline thallium doped bismuth telluride  

SciTech Connect (OSTI)

Nanocrystalline Bismuth telluride and thallium (4 mol %) doped Bismuth telluride were synthesized through hydrothermal method. The as-prepared products were characterized using Powder X-ray Diffraction, High Resolution Transmission Electron Microscopy, Energy Dispersive X-Ray Spectroscopy, UV-Visible spectroscopy and Fourier Transform Infrared Spectroscopy. Powder XRD results revealed the crystalline nature of the obtained phases. HRTEM showed the particle-like morphology of the products. The decrease in the absorption coefficient due to thallium doping was observed in FTIR spectra. The intensity dependent nonlinear optical properties of nanocrystalline bismuth telluride and thallium doped bismuth telluride were studied using the Z-scan technique in open-aperture configuration. Bismuth telluride doped with thallium showed enhanced nonlinear optical response compared to pristine bismuth telluride and hence could be used as a potential candidate for optical power limiting applications. - Graphical Abstract: Nonlinear transmission (Z-scan) curves of nanocrystalline bismuth telluride ({Delta}) and thallium doped bismuth telluride ({open_square}). Thallium doped bismuth telluride showed enhanced nonlinear absorption compared to bismuth telluride. Inset: TEM micrograph of bismuth telluride nanocrystallites. Highlights: Black-Right-Pointing-Pointer Synthesis of Nanocrystalline Bi{sub 2}Te{sub 3} and Thallium doped Bi{sub 2}Te{sub 3} through solvothermal method. Black-Right-Pointing-Pointer Reduced absorption coefficient due to thallium doping found from IR spectroscopy. Black-Right-Pointing-Pointer Open-aperture Z-scan technique for nonlinear optical studies. Black-Right-Pointing-Pointer Two photon absorption based model for theoretical fitting of Z-scan data. Black-Right-Pointing-Pointer Enhanced nonlinear absorption in Thallium doped Bi{sub 2}Te{sub 3} - potential candidate for optical power limiting applications.

Molli, Muralikrishna, E-mail: muralikrishnamolli@sssihl.edu.in [Department of Physics, Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam-515 134 (India); Parola, Sowmendran; Avinash Chunduri, L.A.; Aditha, Saikiran; Sai Muthukumar, V; Mimani Rattan, Tanu; Kamisetti, Venkataramaniah [Department of Physics, Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam-515 134 (India)

2012-05-15T23:59:59.000Z

391

Effect of doping Fe and Si on electronic structure and optical Properties of CdS  

Science Journals Connector (OSTI)

The geometrical structure, electronic properties and optical properties of CdS and M@CdS (M=Fe, Si) were studied systemically with first principles density functional theory. The band structure and density of states have been calculated to analyze the effect of the doping Fe and Si elements on the electronic properties and magnetic properties of CdS. The results show that all the conductive, magnetic and optical properties of CdS are changed by the doped elements. Both obvious and insignificant changes are found in some cases, which provide helpful guide for preparing doped CdS materials.

Yan-Xiao Han; Chuan-Lu Yang; Jun-Sheng Yang; Mei-Shan Wang; Xiao-Guang Ma

2013-01-01T23:59:59.000Z

392

The influence of Cu doping on opto-electronic properties of chemically deposited CdS  

Science Journals Connector (OSTI)

Cadmium sulphide (CdS) thin films were deposited on glass substrate by precipitation from aqueous solution technique. The films were doped with copper using the direct method consisting in the addition of a copper salt (CuCl2) in the deposition bath of CdS. The doped films were annealed in air, at 300°C, for 1 h. We report some structural, optical, electrical and photoelectrical properties of CdS thin films before and after Cu doping, correlated with investigation of trapping levels by Thermally Stimulated Currents (TSC) method.

D Petre; I Pintilie; E Pentia; I Pintilie; T Botila

1999-01-01T23:59:59.000Z

393

Magnetic properties of carbon doped CdS: A first-principles and Monte Carlo study  

Science Journals Connector (OSTI)

Carbon doping of CdS is studied using first-principles calculations and Monte Carlo simulation. Our calculations predict ferromagnetism in C doped CdS, resulting from carbon substitution of sulfur. A single carbon substitution of sulfur favors a spin-polarized state with a magnetic moment of 1.22?B. Ferromagnetic coupling is generally observed between these magnetic moments. A transition temperature of 270K is predicted through Monte Carlo simulation. The ferromagnetism of C doped CdS can be explained by the hole-mediated double exchange mechanism.

Hui Pan; Yuan Ping Feng; Qin Yun Wu; Zhi Gao Huang; Jianyi Lin

2008-03-13T23:59:59.000Z

394

Dynamics of iron-acceptor-pair formation in co-doped silicon  

SciTech Connect (OSTI)

The pairing dynamics of interstitial iron and dopants in silicon co-doped with phosphorous and several acceptor types are presented. The classical picture of iron-acceptor pairing dynamics is expanded to include the thermalization of iron between different dopants. The thermalization is quantitatively described using Boltzmann statistics and different iron-acceptor binding energies. The proper understanding of the pairing dynamics of iron in co-doped silicon will provide additional information on the electronic properties of iron-acceptor pairs and may become an analytical method to quantify and differentiate acceptors in co-doped silicon.

Bartel, T.; Gibaja, F.; Graf, O.; Gross, D.; Kaes, M.; Heuer, M.; Kirscht, F. [Calisolar GmbH, Magnusstrasse 11, 12489 Berlin (Germany)] [Calisolar GmbH, Magnusstrasse 11, 12489 Berlin (Germany); Möller, C. [CiS Forschungsinstitut für Mikrosensorik und Photovoltaik GmbH, Konrad-Zuse-Str. 14, 99099 Erfurt (Germany) [CiS Forschungsinstitut für Mikrosensorik und Photovoltaik GmbH, Konrad-Zuse-Str. 14, 99099 Erfurt (Germany); TU Ilmenau, Institut für Physik, Weimarer Str. 32, 98693 Ilmenau (Germany); Lauer, K. [CiS Forschungsinstitut für Mikrosensorik und Photovoltaik GmbH, Konrad-Zuse-Str. 14, 99099 Erfurt (Germany)] [CiS Forschungsinstitut für Mikrosensorik und Photovoltaik GmbH, Konrad-Zuse-Str. 14, 99099 Erfurt (Germany)

2013-11-11T23:59:59.000Z

395

Enhancing the Electron Mobility via Delta-Doping in SrTiO3  

SciTech Connect (OSTI)

We fabricated high-mobility {delta}-doped structures in SrTiO{sub 3} thin films in order to investigate the low temperature electronic transport properties of confined carriers in this system. An enhancement of the electron mobility above the bulk value was observed as the doped layer thickness decreased. High-field Hall measurements revealed that this mobility enhancement originates from higher-mobility electrons in the undoped clean regions, which have quantum-mechanically broadened from the doped layer. Because of the absence of apparent lattice misfit between the layers, this structure is highly suitable for investigating two-dimensional electron gases in SrTiO{sub 3}

Kozuka, Y.

2011-08-11T23:59:59.000Z

396

Ge doped GaN with controllable high carrier concentration for plasmonic applications  

SciTech Connect (OSTI)

Controllable Ge doping in GaN is demonstrated for carrier concentrations of up to 2.4?×?10{sup 20} cm{sup ?3}. Low temperature luminescence spectra from the highly doped samples reveal band gap renormalization and band filling (Burstein-Moss shift) in addition to a sharp transition. Infrared ellipsometry spectra demonstrate the existence of electron plasma with an energy around 3500?cm{sup ?1} and a surface plasma with an energy around 2000?cm{sup ?1}. These findings open possibilities for the application of highly doped GaN for plasmonic devices.

Kirste, Ronny; Hoffmann, Marc P.; Sachet, Edward; Bobea, Milena; Bryan, Zachary; Bryan, Isaac; Maria, Jon-Paul; Collazo, Ramón; Sitar, Zlatko [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695-7919 (United States)] [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695-7919 (United States); Nenstiel, Christian; Hoffmann, Axel [Institut f?r Festkörperphsyik, TU-Berlin, Hardenbergstrasse 36, 10623 Berlin (Germany)] [Institut f?r Festkörperphsyik, TU-Berlin, Hardenbergstrasse 36, 10623 Berlin (Germany)

2013-12-09T23:59:59.000Z

397

Thermophotovoltaic energy conversion system having a heavily doped n-type region  

DOE Patents [OSTI]

A thermophotovoltaic (TPV) energy conversion semiconductor device is provided which incorporates a heavily doped n-type region and which, as a consequence, has improved TPV conversion efficiency. The thermophotovoltaic energy conversion device includes an emitter layer having first and second opposed sides and a base layer in contact with the first side of the emitter layer. A highly doped n-type cap layer is formed on the second side of the emitter layer or, in another embodiment, a heavily doped n-type emitter layer takes the place of the cap layer.

DePoy, David M. (Clifton Park, NY); Charache, Greg W. (Clifton Park, NY); Baldasaro, Paul F. (Clifton Park, NY)

2000-01-01T23:59:59.000Z

398

Tensile-strain and doping enhanced direct bandgap optical transition of n{sup +} doped Ge/GeSi quantum wells  

SciTech Connect (OSTI)

Band structures of tensile strained and n{sup +} doped Ge/GeSi quantum wells (QWs) are calculated by multiple-band k·p method. The energy dispersion curves of the ? and L conduction subbands are obtained. The effects of tensile strain and n{sup +} doping in Ge on direct bandgap optical gain and spontaneous radiative recombination rate spectra are investigated including the electron leakage from ? to L conduction subbands. Our results show that the optical gain and spontaneous radiative recombination rate can be significantly increased with the tensile strain, n-type doping concentration, and injection carrier density in the Ge QW. The free carrier absorption is calculated and cannot be ignored because of the heavily doped Ge. The pure TM mode polarized net optical gain up to 1153?cm{sup ?1} can be achieved for the Ge/Ge{sub 0.986}Si{sub 0.014} QW with tensile strain of 1.61% and n-type doping concentration of 30?×?10{sup 18}?cm{sup ?3}.

Fan, W. J., E-mail: ewjfan@ntu.edu.sg [NOVITAS, Nanoelectronics Centre of Excellence, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

2013-11-14T23:59:59.000Z

399

Lattice vibrations of pure and doped GaSe  

SciTech Connect (OSTI)

The Bridgman method is used to grow especially undoped and doped single crystals of GaSe. Composition and impurity content of the grown crystals were determined using X-ray fluorescence (XRF) method. X-ray diffraction, Raman scattering, photoluminescence (PL), and IR transmission measurements were performed at room temperature. The long wavelength lattice vibrations of four modifications of GaSe were described in the framework of modified one-layer linear-chain model which also takes into consideration the interaction of the selenium (Se) atom with the second nearest neighbor gallium (Ga) atom in the same layer. The existence of an eight-layer modification of GaSe is suggested and the vibrational frequencies of this modification are explained in the framework of a lattice dynamical model considered in the present work. Frequencies and the type of vibrations (gap, local, or resonance) for the impurity atoms were calculated and compared with the experimental results.

Allakhverdiev, K. [Materials Institute, Marmara Research Center, TUBITAK, Gebze/Kocaeli 41470 (Turkey) and Institute of Physics, Azerbaijan National Academy of Sciences, Baku AZ1143 (Azerbaijan)]. E-mail: kerim.allahverdi@mam.gov.tr; Baykara, T. [Materials Institute, Marmara Research Center, TUBITAK, Gebze/Kocaeli 41470 (Turkey); Ellialtioglu, S. [Department of Physics, Middle East Technical University, Ankara 06531 (Turkey); Hashimzade, F. [Institute of Physics, Azerbaijan National Academy of Sciences, Baku AZ1143 (Azerbaijan); Huseinova, D. [Institute of Physics, Azerbaijan National Academy of Sciences, Baku AZ1143 (Azerbaijan); Kawamura, K. [Institute of Materials Science, University of Tsukuba 305-8573 (Japan); Kaya, A.A. [Materials Institute, Marmara Research Center, TUBITAK, Gebze/Kocaeli 41470 (Turkey); Kulibekov, A.M. [Department of Physics, Mugla University, Mugla 48000 (Turkey); Onari, S. [Institute of Materials Science, University of Tsukuba 305-8573 (Japan)

2006-04-13T23:59:59.000Z

400

Chemical vapor deposition of boron-doped hydrogenated amorphous silicon  

SciTech Connect (OSTI)

Deposition conditions and film properties for a variety of boron-doped hydrogenated amorphous silicon films and silicon-carbon films produced by chemical vapor deposition (CVD) are discussed. Deposition gases include monosilane, disilane, trisilane, and acetylene. Two types of optically wide band-gap p layers are obtained. One of these window p layers (without carbon) has been extensively tested in photovoltaic devices. Remarkably, this p layer can be deposited between about 200 to 300 /sup 0/C. A typical open circuit voltage in an all CVD p-i-n device is 0.70--0.72 V, and in a hybrid device where the i and n layers are deposited by glow discharge, 0.8--0.83 V.

Ellis F.B. Jr.; Delahoy, A.E.

1985-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Welding and Weldability of Thorium-Doped Iridium Alloys  

SciTech Connect (OSTI)

Ir-0.3%W alloys doped with thorium are currently used as post-impact containment material for radioactive fuel in thermoelectric generators that provide stable electrical power for a variety of outer planetary space exploration missions. Welding and weldability of a series of alloys was investigated using arc and laser welding processes. Some of these alloys are prone to severe hot-cracking during welding. Weldability of these alloys was characterized using Sigmajig weldability test. Hot-cracking is influenced to a great extent by the fusion zone microstructure and composition. Thorium content and welding atmosphere were found to be very critical. The weld cracking behavior in these alloys can be controlled by modifying the fusion zone microstructure. Fusion zone microstructure was found to be controlled by welding process, process parameters, and the weld pool shape.

David, S.A.; Ohriner, E.K.; King, J.F.

2000-03-12T23:59:59.000Z

402

Infrared luminescence from silicon nanostructures heavily doped with boron  

SciTech Connect (OSTI)

Intense highly polarized radiation from silicon nanostructures heavily doped with boron to 5 Multiplication-Sign 10{sup 21} cm{sup -3} is studied as a function of temperature, forward current, and an additional lateral electric field. The features of the radiation intensity and degree of polarization suggest that an important role in the formation of the luminescence spectra is played by the ordered system of B{sup +}-B{sup -} dipoles, formed as a result of the reconstruction of shallow boron acceptors as centers with negative correlation energy. The results obtained are interpreted within a proposed model based on two-electron adiabatic potentials, according to which radiation results from donor-acceptor recombination via boron dipole center states, involving shallow phosphorus donors.

Bagraev, N. T.; Klyachkin, L. E.; Kuzmin, R. V., E-mail: roman.kuzmin@mail.ioffe.ru; Malyarenko, A. M. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation); Mashkov, V. A. [Saint Petersburg State Polytechnical University (Russian Federation)

2012-03-15T23:59:59.000Z

403

Gain properties of dye-doped polymer thin films  

E-Print Network [OSTI]

The demonstration of an electrically pumped organic laser remains a major issue of organic optoelectronics for several decades. Nowadays, hybrid pumping seems a promising compromise where the organic material is optically pumped by an electrically pumped inorganic device on chip. This technical solution requires therefore an optimization of the organic gain medium under optical pumping. Here, we report a detailed study of gain features of dye-doped polymer thin films, in particular we introduce the gain efficiency $K$, in order to facilitate comparison between material and experimental conditions. First, we measure the bulk gain by the means of a pump-probe setup, and then present in details several factors which modify the actual gain of the layer, namely the confinement factor, the pump polarization, the molecular anisotropy, and the re-absorption. The usual model to evaluate the gain leads to an overestimation by more than one order of magnitude, which stresses the importance to design the devices accordin...

Gozhyk, I; Rabbani, H; Djellali, N; Forget, S; Chenais, S; Ulysse, C; Brosseau, A; Gauvin, S; Zyss, J; Lebental, M

2014-01-01T23:59:59.000Z

404

Unlocking doping and compositional profiles of nanowire ensembles using SIMS  

Science Journals Connector (OSTI)

Dynamic and time-of-flight (TOF) secondary ion mass spectrometry (SIMS) was performed on vertically standing III–V nanowire ensembles embedded in Cyclotene polymer. By embedding the NWs in Cyclotene, the top surface of the sample was made planar, while the space between the NWs was filled to protect the background substrate from the ion beam, thus allowing for the NWs to be sputtered and analyzed evenly as a function of depth. Using thin film standards, SIMS analysis was used to calculate the impurity dopant concentration as a function of height in the NW ensemble. This marked the first use of conventional SIMS to accurately determine the doping density with excellent depth resolution. Additionally, this is the first presentation of SIMS as the only reported tool for characterizing the segment height uniformity of any arbitrary axial heterostructure NW ensemble.

A C E Chia; J P Boulanger; R R LaPierre

2013-01-01T23:59:59.000Z

405

Pulsed energy synthesis and doping of silicon carbide  

DOE Patents [OSTI]

A method for producing beta silicon carbide thin films by co-depositing thin films of amorphous silicon and carbon onto a substrate is disclosed, whereafter the films are irradiated by exposure to a pulsed energy source (e.g. excimer laser) to cause formation of the beta-SiC compound. Doped beta-SiC may be produced by introducing dopant gases during irradiation. Single layers up to a thickness of 0.5-1 micron have been produced, with thicker layers being produced by multiple processing steps. Since the electron transport properties of beta silicon carbide over a wide temperature range of 27--730 C is better than these properties of alpha silicon carbide, they have wide application, such as in high temperature semiconductors, including HETEROJUNCTION-junction bipolar transistors and power devices, as well as in high bandgap solar arrays, ultra-hard coatings, light emitting diodes, sensors, etc.

Truher, J.B.; Kaschmitter, J.L.; Thompson, J.B.; Sigmon, T.W.

1995-06-20T23:59:59.000Z

406

Pulsed energy synthesis and doping of silicon carbide  

DOE Patents [OSTI]

A method for producing beta silicon carbide thin films by co-depositing thin films of amorphous silicon and carbon onto a substrate, whereafter the films are irradiated by exposure to a pulsed energy source (e.g. excimer laser) to cause formation of the beta-SiC compound. Doped beta-SiC may be produced by introducing dopant gases during irradiation. Single layers up to a thickness of 0.5-1 micron have been produced, with thicker layers being produced by multiple processing steps. Since the electron transport properties of beta silicon carbide over a wide temperature range of 27.degree.-730.degree. C. is better than these properties of alpha silicon carbide, they have wide application, such as in high temperature semiconductors, including hetero-junction bipolar transistors and power devices, as well as in high bandgap solar arrays, ultra-hard coatings, light emitting diodes, sensors, etc.

Truher, Joel B. (San Rafael, CA); Kaschmitter, James L. (Pleasanton, CA); Thompson, Jesse B. (Brentwood, CA); Sigmon, Thomas W. (Beaverton, OR)

1995-01-01T23:59:59.000Z

407

Enhanced superconducting pairing interaction in indium-doped tin telluride  

SciTech Connect (OSTI)

The ferroelectric degenerate semiconductor Sn{sub 1-{delta}}Te exhibits superconductivity with critical temperatures, T{sub c}, of up to 0.3 K for hole densities of order 10{sup 21} cm{sup -3}. When doped on the tin site with greater than x{sub c} = 1.7(3)% indium atoms, however, superconductivity is observed up to 2 K, though the carrier density does not change significantly. We present specific heat data showing that a stronger pairing interaction is present for x > x{sub c} than for x < x{sub c}. By examining the effect of In dopant atoms on both T{sub c} and the temperature of the ferroelectric structural phase transition, T{sub SPT}, we show that phonon modes related to this transition are not responsible for this T{sub c} enhancement, and discuss a plausible candidate based on the unique properties of the indium impurities.

Erickson, A.S.

2010-05-03T23:59:59.000Z

408

Enhanced superconducting pairing interaction in indium-doped tin telluride  

SciTech Connect (OSTI)

The ferroelectric degenerate semiconductor Sn{sub 1-{delta}}Te exhibits superconductivity with critical temperatures, T{sub c}, of up to 0.3 K for hole densities of order 10{sup 21} cm{sup -3}. When doped on the tin site with greater than x{sub c} = 1.7(3)% indium atoms, however, superconductivity is observed up to 2 K, though the carrier density does not change significantly. We present specific heat data showing that a stronger pairing interaction is present for x > x{sub c} than for x < x{sub c}. By examining the effect of In dopant atoms on both T{sub c} and the temperature of the ferroelectric structural phase transition, T{sub SPT}, we show that phonon modes related to this transition are not responsible for this T{sub c} enhancement, and discuss a plausible candidate based on the unique properties of the indium impurities.

Erickson, A.S.; Chu, J.-H.; /Stanford U., Appl. Phys. Dept. /Stanford U., Geballe Lab.; Toney, M.F.; Geballe, T.H.; Fisher, I.R.; /SLAC, SSRL /Stanford U., Appl. Phys. Dept. /Stanford U., Geballe Lab.

2010-02-15T23:59:59.000Z

409

Gas-self-filter-based erbium-doped fiber loop laser for gas detection  

Science Journals Connector (OSTI)

An erbium-doped fiber (EDF) loop laser, based on a gas-self-filter (GSF), is developed with single or multiple wavelength emission. The GSF is a type of Mach–Zehnder...

Guo, Kaikai; Lou, Xiutao; Yan, Chunsheng; Mei, Liang

2014-01-01T23:59:59.000Z

410

Disilane: A new silicon doping source in metalorganic chemical vapor deposition of GaAs  

Science Journals Connector (OSTI)

Disilane (Si2H6) is presented as a new silicon doping source in the metalorganic chemical vapor deposition of GaAs together with comparison results obtained using the conventional silane (SiH4) doping source. The dopingcharacteristics of disilane were studied over a wide range of growth conditions: temperature gas phase stoichiometry and disilane concentration in the growth ambient. Silicon incorporation by means of disilane pyrolysis showed no temperature dependence in sharp contrast to the strong temperature activated dependence found when employing silane. The decomposition reaction of disilane proved to be very efficient reducing the amount of dopant gas required by about two orders of magnitude at the lower growth temperatures. Electrical measurements on disilane?doped GaAs yield the same high mobilities as obtained in silane?doped GaAs films indicative of low compensation.

T. F. Kuech; B. S. Meyerson; E. Veuhoff

1984-01-01T23:59:59.000Z

411

New Materials of Co-Doped ZnO for LEDs and Thin Films Solar Cells  

Science Journals Connector (OSTI)

Zr-Al co-doped ZnO were prepared by DC magnetron sputtering on glass substrates. Microstructure, optoelectrical properties of the films were investigated. The films with resistivity...

Yuan, Yuzhen; Wang, Hui

412

Anomalous Fermi-Surface Dependent Pairing in a Self-Doped High-Tc Superconductor  

SciTech Connect (OSTI)

We report the discovery of a self-doped multi-layer high T{sub c} superconductor Ba{sub 2}Ca{sub 3}Cu{sub 4}O{sub 8}F{sub 2} (F0234) which contains distinctly different superconducting gap magnitudes along its two Fermi surface(FS) sheets. While formal valence counting would imply this material to be an undoped insulator, it is a self-doped superconductor with a T{sub c} of 60K, possessing simultaneously both electron- and hole-doped FS sheets. Intriguingly, the FS sheet characterized by the much larger gap is the electron-doped one, which has a shape disfavoring two electronic features considered to be important for the pairing mechanism: the van Hove singularity and the antiferromagnetic ({pi}/a, {pi}/a) scattering.

Chen, Y.

2010-05-03T23:59:59.000Z

413

Anomalous Fermi-Surface Dependent Pairing in a Self-Doped High-T(c) Superconductor  

SciTech Connect (OSTI)

We report the discovery of a self-doped multilayer high T{sub c} superconductor Ba{sub 2}Ca{sub 3}Cu{sub 4}O{sub 8}F{sub 2} (F0234) which contains distinctly different superconducting gap magnitudes along its two Fermi-surface sheets. While formal valence counting would imply this material to be an undoped insulator, it is a self-doped superconductor with a T{sub c} of 60 K, possessing simultaneously both electron- and hole-doped Fermi-surface sheets. Intriguingly, the Fermi-surface sheet characterized by the much larger gap is the electron-doped one, which has a shape disfavoring two electronic features considered to be important for the pairing mechanism: the van Hove singularity and the antiferromagnetic ({pi}/{alpha}, {pi}/{alpha}) scattering.

Chen, Yulin; Iyo, Akira; Yang, Wanli; Zhou, Xingjiang; Lu, Donghui; Eisaki, Hiroshi; Devereaux, Thomas P.; Hussain, Zahid; Shen, Z.-X.; /Stanford U., Phys. Dept. /SLAC,

2007-02-12T23:59:59.000Z

414

Mg-Doped ZnO Nanoparticles for Efficient Sunlight-Driven Photocatalysis  

Science Journals Connector (OSTI)

Magnesium-doped ZnO (ZMO) nanoparticles were synthesized through an oxalate coprecipitation method. Crystallization of ZMO upon thermal decomposition of the oxalate precursors was investigated using differential scanning calorimetry (DSC) and X-ray ...

Vinodkumar Etacheri; Roshith Roshan; Vishwanathan Kumar

2012-05-03T23:59:59.000Z

415

Electronic and magnetic properties of Fe and Mn doped two dimensional hexagonal germanium sheets  

SciTech Connect (OSTI)

Using first principles density functional theory calculations, the present paper reports systematic total energy calculations of the electronic properties such as density of states and magnetic moment of pristine and iron and manganese doped two dimensional hexagonal germanium sheets.

Soni, Himadri R., E-mail: himadri.soni@gmail.com; Jha, Prafulla K., E-mail: himadri.soni@gmail.com [Department of Physics, Maharaja Krishnakumarsinhji Bhavnagar University, Bhavnagar-364001 (India)

2014-04-24T23:59:59.000Z

416

Graphene-based passively Q-switched dual-wavelength erbium-doped fiber laser  

Science Journals Connector (OSTI)

We demonstrate a compact Q-switched dual-wavelength erbium-doped fiber (EDF) laser based on graphene as a saturable absorber (SA). By optically driven deposition of graphene on a...

Luo, Zhengqian; Zhou, Min; Weng, Jian; Huang, Guoming; Xu, Huiying; Ye, Chenchun; Cai, Zhiping

2010-01-01T23:59:59.000Z

417

Negative differential resistance behavior in phosphorus-doped armchair graphene nanoribbon junctions  

SciTech Connect (OSTI)

In this present work, we investigate the electronic transport properties of phosphorus-doped armchair graphene nanoribbon (AGNR) junctions by employing nonequilibrium Green's functions in combination with the density-function theory. Two phosphorus (P) atoms are considered to substitute the central carbon atom with the different width of AGNRs. The results indicate that the electronic transport behaviors are strongly dependent on the width of the P-doped graphene nanoribbons. The current-voltage characteristics of the doped AGNR junctions reveal an interesting negative differential resistance (NDR) and exhibit three distinct family (3 n, 3 n + 1, 3 n + 2) behaviors. These results display that P doping is a very good way to achieve NDR of the graphene nanoribbon devices.

Zhou, Yuhong [School of Optical and Electronic Information, Huazhong University of Science and Technology, No. 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China); Wenhua College, Huzhong University of Science and Technology, Wuhan City, Hubei Province 430074 (China); Zhang, Daoli, E-mail: zhang-daoli@hust.edu.cn; Zhang, Jianbing; Miao, Xiangshui [School of Optical and Electronic Information, Huazhong University of Science and Technology, No. 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China); Wuhan National Laboratory for Optoelectronics, 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China); Ye, Cong [Faculty of Physics and Electronic Technology, Hubei University, Wuhan 430062 (China)

2014-02-21T23:59:59.000Z

418

Photoconductivity of CdS films, undoped and doped with alkali-metal impurity ions  

Science Journals Connector (OSTI)

The nonequilibrium electron processes that occur during photoconductivity increase and relaxation in pyrolytic CdS films, both nominally undoped and doped with alkali metals, are studied. The...S...-shaped or exh...

T. L. Mayorova; V. G. Klyuev; J. S. Bezdetko

2014-07-01T23:59:59.000Z

419

Synthesis, structural and photocatalytic studies of Mn-doped CdS nanoparticles  

Science Journals Connector (OSTI)

Mn-doped CdS nanoparticles (Cd1?x Mn x S; where x...= 0.00–0.10) were synthesized by a chemical precipitation method. The synthesized products were characterized ...

Ruby Chauhan; Ashavani Kumar; Ram Pal Chaudhary

2013-02-01T23:59:59.000Z

420

Optical, electrochemical and thermal properties of Co2+-doped CdS nanoparticles using polyvinylpyrrolidone  

Science Journals Connector (OSTI)

Co2+ (1–5 and 10 %)-doped cadmium sulfide nanoparticles were synthesized by the ... that Co ions were successfully incorporated into the CdS lattice and the transmission electron microscopy results ... of all the...

S. Muruganandam; G. Anbalagan; G. Murugadoss

2014-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Ferromagnetism in Gd-doped CdS dilute magnetic semiconducting nanorods  

Science Journals Connector (OSTI)

Cd x Gd1?x S (x...= 0–0.15) nanorods have been synthesized by solvothermal technique. X-ray diffraction study reveals that pure and Gd-doped CdS nanorods exhibits...

Kamaldeep Kaur; Gurmeet Singh Lotey…

2014-01-01T23:59:59.000Z

422

A Study of CdS and Ag doped CdS Prepared through CBD Technique  

Science Journals Connector (OSTI)

A novel and simple CBD Technique has been utilized to synthesize CdS and Ag doped CdS nanoparticles and thin film with an average particle size of 7nm, characterized by X-RD,...

Chandel, Shubham

423

Effect of indium doping and annealing on photoconducting property of wurtzite type CdS  

Science Journals Connector (OSTI)

In this paper we observed the effect of doping and annealing on the dark current and anomalous photoconducting behavior of hexagonal wurtzite CdS, synthesized by solid state reaction method. Undoped CdS sample sh...

Vineet Kumar Singh; Pratima Chauhan; Sheo Kumar Mishra…

2012-06-01T23:59:59.000Z

424

Structural and dielectrical studies on mechano-chemically synthesized indium doped CdS nanopowders  

Science Journals Connector (OSTI)

Incorporation of indium (dopant) into CdS crystals have been successfully achieved by a ... ray diffraction (XRD) analysis of milled In doped CdS compound showed that the major phase of ... good pathway to identi...

B. J. Babu; S. Velumani; A. Kassiba

2011-08-01T23:59:59.000Z

425

Photoconductivity of chemically deposited rare-earth-doped CdS films  

Science Journals Connector (OSTI)

Highly photosensitive films with photocurrent to dark current ratios of the order of 105 have been prepared by doping CdS with Nd and Pr. The conditions for...

S. Bhushan; Dipti Thakur

1992-03-01T23:59:59.000Z

426

In situ nitrogen-doped graphene grown from polydimethylsiloxane by plasma enhanced chemical vapor deposition  

SciTech Connect (OSTI)

Due to its unique electronic properties and wide spectrum of promising applications, graphene has attracted much attention from scientists in various fields. Control and engineering of graphene’s semiconducting properties is considered to be the key of its applications in electronic devices. Here, we report a novel method to prepare in situ nitrogen-doped graphene by microwave plasma assisted chemical vapor deposition (CVD) using PDMS (Polydimethylsiloxane) as a solid carbon source. Based on this approach, the concentration of nitrogen-doping can be easily controlled via the flow rate of nitrogen during the CVD process. X-ray photoelectron spectroscopy results indicated that the nitrogen atoms doped into graphene lattice were mainly in the forms of pyridinic and pyrrolic structures. Moreover, first-principles calculations show that the incorporated nitrogen atoms can lead to p-type doping of graphene. This in situ approach provides a promising strategy to prepare graphene with controlled electronic properties.

Wang, Chundong; Zhou, Yungang; He, Lifang; Ng, Tsz-Wai; Hong, Guo; Wu, Qi-Hui; Gao, Fei; Lee, Chun-Sing; Zhang, Wenjun

2013-01-21T23:59:59.000Z

427

Plasmonic Figures of Merit in a Doped Graphene Sheet | MIT-Harvard...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Plasmonic Figures of Merit in a Doped Graphene Sheet May 15, 2014 at 2pm36-428 Marco Polini NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore di Pisa MarcoPolini...

428

E-Print Network 3.0 - al-doped zno thin Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the E2(high) mode on annealed samples indicates that the crystalline quality of the ZnO thin... of nanostructured Al-doped zinc oxide films on Si for solar cells applications, Sol....

429

Cryogenic Yb3+-doped materials for pulsed solid-state laser applications [Invited  

Science Journals Connector (OSTI)

We review recent progress in pulsed lasers using cryogenically-cooled Yb3+-doped gain media, with an emphasis on high average power. Recent measurements of thermo-optic...

Rand, Darren; Miller, Daniel; Ripin, Daniel J; Fan, Tso Yee

2011-01-01T23:59:59.000Z

430

Preparation and sintering of silica-doped zirconia by colloidal processing  

SciTech Connect (OSTI)

Silica-doped (SiO{sub 2} = 0--1.0 mass%) zirconia (3 mol% Y{sub 2}O{sub 3}-doped tetragonal ZrO{sub 2}) compacts are prepared from hetero-coagulated and well-dispersed suspensions by colloidal processing. The suspensions are consolidated by a pressure filtration technique. The green density of the compacts consolidated from the well-dispersed suspensions is higher than that from the hetero-coagulated suspensions. The lower density of the latter compacts is improved by a subsequent cold isostatic pressing (CIP) at 400 MPa. The sinterability of the compacts at 1,200 C is greatly affected by the amount of doped silica. The densification and grain growth are hindered by silica doping above 0.3 wt% at 1,200 C. All the compacts are densificated to a relative density of above 99% by sintering at 1,300 C for 2 h.

Uchikoshi, T.; Sakka, Y.; Ozawa, K.; Hiraga, K. [National Research Inst. for Metals, Tsukuba, Ibaraki (Japan)

1997-09-01T23:59:59.000Z

431

JOURNAL OF MATERIALS SCIENCE 36 (2001) 77 86 Synthesis of yttria-doped strontium-zirconium  

E-Print Network [OSTI]

JOURNAL OF MATERIALS SCIENCE 36 (2001) 77­ 86 Synthesis of yttria-doped strontium-zirconium oxide densification, than co-precipitated powders. C 2001 Kluwer Academic Publishers 1. Introduction Strontium

Iglesia, Enrique

432

Chemical Expansion and Frozen-In Oxygen Vacancies in Pr-Doped Ceria  

E-Print Network [OSTI]

Doped CeO2 is a promising candidate for solid oxide fuel cell electrolyte and electrode applications because of its high ionic conductivity and reduction/oxidation behavior at intermediate temperatures. Its electronic and ...

Kuru, Yener

2011-01-01T23:59:59.000Z

433

A new class of high ZT doped bulk nanothermoelectrics through bottom-up synthesis  

Broader source: Energy.gov [DOE]

Reports on synthesis of large quantities of p- and n-type nanocrystals then sintered into bulk samples with high power factors and low thermal conductivity through impurity doping and nanostructuring

434

Boron- and phosphorus-doped polycrystalline silicon thin films prepared by silver-induced layer exchange  

SciTech Connect (OSTI)

Intentional boron and phosphorus doping of polycrystalline silicon thin films on glass prepared by the silver-induced layer exchange is presented. A silver/(titanium) oxide/amorphous silicon stack is annealed at temperatures below the eutectic temperature of the Ag/Si system, leading to a complete layer exchange and simultaneous crystallization of the amorphous silicon. Intentional doping of the amorphous silicon prior to the exchange process results in boron- or phosphorus-doped polycrystalline silicon. Hall effect measurements show carrier concentrations between 2 Multiplication-Sign 10{sup 17} cm{sup -3} and 3 Multiplication-Sign 10{sup 20} cm{sup -3} for phosphorus and 4 Multiplication-Sign 10{sup 18} cm{sup -3} to 3 Multiplication-Sign 10{sup 19} cm{sup -3} for boron-doped layers, with carrier mobilities up to 90 cm{sup 2}/V s.

Antesberger, T.; Wassner, T. A.; Jaeger, C.; Algasinger, M.; Kashani, M.; Scholz, M.; Matich, S.; Stutzmann, M. [Walter Schottky Institut and Physics Department, Technische Universitaet Muenchen, Am Coulombwall 4, 85748 Garching (Germany)] [Walter Schottky Institut and Physics Department, Technische Universitaet Muenchen, Am Coulombwall 4, 85748 Garching (Germany)

2013-05-27T23:59:59.000Z

435

Raman spectroscopy study of heat-treated and boron-doped double wall carbon nanotubes  

E-Print Network [OSTI]

We performed Raman spectroscopy experiments on undoped and boron-doped double walled carbon nanotubes (DWNTs) that exhibit the “coalescence inducing mode” as these DWNTs are heat treated to temperatures between 1200 °C ...

Villalpando Paez, Federico

436

Coherence and Pairing in a Doped Mott Insulator: Application to the Cuprates  

E-Print Network [OSTI]

The issues of single particle coherence and its interplay with singlet pairing are studied within the slave boson gauge theory of a doped Mott insulator. Prior work by one of us [T. Senthil, Phys. Rev. B 78, 045109 (2008)] ...

Lee, Patrick A.

437

Engineering the magnetic properties of the Mn13 cluster by doping  

E-Print Network [OSTI]

With a goal to produce a giant magnetic moment in a Mn13 cluster that will be useful for practical applications, we have considered the structure and magnetic properties of a pure Mn13 cluster and substitutionally doped ...

Datta, Soumendu

438

Cladding pumped large-mode-area Nd-doped holey fiber laser  

Science Journals Connector (OSTI)

A large Nd-doped core placed in a microstructure cladding (holey fiber) was pumped with a low-brightness diode laser. The area ratio of the pump radiation on the fiber to the core...

Glas, Peter; Fisher, D

2002-01-01T23:59:59.000Z

439

The Influence of Doping on the Performance of Terahertz Quantum-Cascade-Lasers  

Science Journals Connector (OSTI)

We present the effects of the doping concentration on a set of terahertz quantum-cascade-lasers emitting around 2.75 THz. The threshold current density decreases linearly with the...

Benz, Alexander; Fasching, Gernot; Andrews, Aaron Maxwell; Unterrainer, Karl; Roch, Tomas; Schrenk, Werner; Strasser, Gottfried

440

Yb-doped Large Pitch Fiber with 105µm Mode Field Diameter  

Science Journals Connector (OSTI)

We present an active Yb-doped Large Pitch Fiber with 105µm mode field diameter. It was tested in a fiber CPA system delivering <500fs, 2mJ pulses with 3.8GW peak power. The...

Jansen, Florian; Stutzki, Fabian; Eidam, Tino; Rothhardt, Jan; Hädrich, Steffen; Carstens, Henning; Jauregui, Cesar; Limpert, Jens; Tünnermann, Andreas

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Nanoscale Interplay of Strain and Doping in a High-Temperature Superconductor  

Science Journals Connector (OSTI)

The highest-temperature superconductors are electronically inhomogeneous at the nanoscale, suggesting the existence of a local variable that could be harnessed to enhance the superconducting pairing. Here we report the relationship between local doping ...

Ilija Zeljkovic; Jouko Nieminen; Dennis Huang; Tay-Rong Chang; Yang He; Horng-Tay Jeng; Zhijun Xu; Jinsheng Wen; Genda Gu; Hsin Lin; Robert S. Markiewicz; Arun Bansil; Jennifer E. Hoffman

2014-11-03T23:59:59.000Z

442

Enhancement of electro-optic properties in liquid crystal devices via titanium nanoparticle doping  

Science Journals Connector (OSTI)

We investigated the properties of nematic liquid crystal device (NLC) doped with titanium (Ti) nanoparticle (~100nm). The electro-optic (EO) properties of LCs changed according to Ti...

Ha, Yong-Seok; Kim, Hyung-Jun; Park, Hong-Gyu; Seo, Dae-Shik

2012-01-01T23:59:59.000Z

443

Energy conversion in Er3+ doped chalcogenide fibers for gas optical sensor  

Science Journals Connector (OSTI)

Er3+ doped chalcogenide fibers are used to convert a 4.3 µm optical signal into an 800 nm radiation with the aim of developing an all-optical infrared gas sensor with a detection in...

Anne-Laure, Pelé; Doualan, Jean-Louis; Braud, Alain; Nazabal, Virginie; Moncorgé, Richard; Camy, Patrice

444

High-temperature thermoelectric response of double-doped SrTiO3 epitaxial films  

Science Journals Connector (OSTI)

SrTiO3 is a promising n-type oxide semiconductor for thermoelectric energy conversion. Epitaxial thin films of SrTiO3 doped with both La and oxygen vacancies have been synthesized by pulsed laser deposition. The thermoelectric and galvanomagnetic properties of these films have been characterized at temperatures ranging from 300 to 900 K and are typical of a doped semiconductor. Thermopower values of double-doped films are comparable to previous studies of La-doped single crystals at similar carrier concentrations. The highest thermoelectric figure of merit (ZT) was measured to be 0.28 at 873 K at a carrier concentration of 2.5×1021?cm?3.

J. Ravichandran; W. Siemons; D.-W. Oh; J. T. Kardel; A. Chari; H. Heijmerikx; M. L. Scullin; A. Majumdar; R. Ramesh; D. G. Cahill

2010-10-28T23:59:59.000Z

445

E-Print Network 3.0 - aluminum-doped zinc oxide Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

for the first time at 800 Torr... reserved. Keywords: Transparent-conducting oxide (TCO); AlZnO; PECVD 1. Introduction Aluminum-doped zinc... PECVD for the deposition of ......

446

Al-doped ZnO powdered materials: Al solubility limit and IR absorption properties  

Science Journals Connector (OSTI)

Al-doped ZnO powder was synthesized via the Pechini route with a doping rate varying from 1 to 4 mol.%. A solubility limit has been estimated under 0.3 mol.% of Al using X-ray diffraction refinements. The incorporation of aluminium into the ZnO lattice was investigated by 27Al NMR, which suggests an extremely low amount of Al in a distribution of sites in ZnO. In order to assess the impact of such a low dopant amount, diffuse reflection experiments were performed for a wavelength range from 200 to 2500 nm. If the effect of doping was negligible for samples prepared at 850 °C, annealing at 1200 °C clearly reveals enhanced IR absorption properties for the doped samples, which are similar whatever be the nominal Al content.

Hélène Serier; Manuel Gaudon; Michel Ménétrier

2009-01-01T23:59:59.000Z

447

E-Print Network 3.0 - aluminum doped zinc Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and Ecology 10 Growth and photoluminescence studies of Zn-doped AlN epilayers N. Nepal, M. L. Nakarmi, H. U. Jang, J. Y. Lin, and H. X. Jianga Summary: Growth and...

448

Characteristics of 6H-silicon carbide PIN diodes prototyping by laser doping  

Science Journals Connector (OSTI)

Silicon carbide PIN diodes have been fabricated using a direct-write laser-doping technique that reduces defect generation compared to the conventional ion-implantation technique. Nitrogen and aluminum were su...

Z. Tian; N. R. Quick; A. Kar

2005-01-01T23:59:59.000Z

449

Dielectric and electromechanical properties of barium and zirconium co-doped sodium bismuth titanate  

E-Print Network [OSTI]

Compositional exploration was conducted within the alkaline bismuth titanate system by doping on the A- and B- sites with Ba?² and Zr??, respectively. Results on the phase, dielectric and electromechanical properties of ...

Sheets, Sossity A. (Sossity Amber), 1973-

2000-01-01T23:59:59.000Z

450

Silicon-germanium saturable absorbers and erbium-doped waveguides for integrated mode-locked lasers  

E-Print Network [OSTI]

In this thesis, Silicon-Germanium (SiGe) Saturable Bragg Reflectors (SBR) and Erbium-doped waveguide chips are fabricated and characterized as crucial components for integration of a mode-locked laser on a Si-chip. The ...

Byun, Hyunil

2006-01-01T23:59:59.000Z

451

E-Print Network 3.0 - al doped zno Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Chow, Lee - Department of Physics, University of Central Florida Collection: Physics ; Materials Science 28 Charge carrier and spin doping in ZnO thin films D.P. Norton a,*, M....

452

High-energy Laser Amplifiers using Ultra-broad Emitting Yb-doped Materials  

Science Journals Connector (OSTI)

High-energy laser amplifiers using Yb-doped gain media often show reduced efficiencies especially when operating at ultra-short pulses. We summarize techniques to improve storage and...

Siebold, Mathias; Loeser, Markus; Roeser, Fabian; Uecker, Reinhard; Koerner, Joerg; Hein, Joachim; Hornung, Marco; Kaluza, Malte; Schramm, Ulrich

453

Nitrogen doping in pulsed laser deposited ZnO thin films using dense plasma focus  

Science Journals Connector (OSTI)

Pulsed laser deposition synthesized ZnO thin films, grown at 400 °C substrate temperature in different oxygen gas pressures, were irradiated with 6 shots of pulsed nitrogen ions obtained from 2.94 kJ dense plasma focus to achieve the nitrogen doping in ZnO. Structural, compositional and optical properties of as-deposited and nitrogen ion irradiated ZnO thin films were investigated to confirm the successful doping of nitrogen in irradiated samples. Spectral changes have been seen in the nitrogen irradiated ZnO thin film samples from the low temperature PL measurements. Free electron to acceptor emissions can be observed from the irradiated samples, which hints towards the successful nitrogen doping in films. Compositional analysis by X-ray photoelectron spectroscopy and corresponding shifts in binding energy core peaks of oxygen and nitrogen confirmed the successful use of plasma focus device as a novel source for nitrogen ion doping in ZnO thin films.

S. Karamat; R.S. Rawat; T.L. Tan; P. Lee; S.V. Springham; E. Ghareshabani; R. Chen; H.D. Sun

2011-01-01T23:59:59.000Z

454

Understanding the viability of impurity-band photovoltaics : a case study of S-doped Si  

E-Print Network [OSTI]

This thesis explores the electronic structure, optical properties, and carrier lifetimes in silicon that is doped with sulfur beyond the equilibrium solid solubility limit, with a focus on applications as an absorber layer ...

Sullivan, Joseph Timothy, Ph. D. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

455

Generation of high power, high repetition-rate pulses using erbium-doped fiber ring laser  

E-Print Network [OSTI]

This thesis presents the results obtained from crographics. generation of high repetition rate, high peak power output pulses using an erbium-doped fiber amplifier (EDFA). Two configurations were employed. The first setup used a linear cavity...

Hinson, Brett Darren

2012-06-07T23:59:59.000Z

456

Microsoft Word - JMatyas_The Effects of Glass Doping _MST'13...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

EFFECTS OF GLASS DOPING, TEMPERATURE AND TIME ON THE MORPHOLOGY, COMPOSITION, AND IRON REDOX OF SPINEL CRYSTALS J. Maty 1 , J. E. Amonette 1 , R. K. Kukkadapu 1 , D. Schreiber...

457

Time-resolved plasma measurements in Ge-doped silica exposed to infrared femtosecond laser  

SciTech Connect (OSTI)

Using a time-resolved interferometric technique, we study the laser-induced carrier-trapping dynamics in SiO{sub 2} and Ge-doped SiO{sub 2}. The fast trapping of electrons in the band gap is associated with the formation of self-trapped excitons (STE). The STE trapping is doping dependent in SiO{sub 2}. The mean trapping time of electrons excited in the conduction band was found to be significantly lower in Ge-doped silica (75 {+-} 5 fs) when compared to pure silica (155 {+-} 5 fs). At our concentration level, this indicates that the plasma properties are determined by the presence of easily ionizable states such as the presence of Ge atoms in the glass network. Therefore, we suggest that in Ge-doped silica there exist an additional trapping pathway that leads to a significantly faster excitons trapping and a higher plasma density when compared to undoped silica.

Lancry, M.; Poumellec, B. [LPCES/ICMMO, UMR CNRS-UPS 8182, Universite Paris Sud 11, Batiment 410, 91405 Orsay (France); Groothoff, N.; Canning, J. [Interdisciplinary Photonics Laboratories, School of Chemistry, University of Sydney, 206 NIC, ATP, Eveleigh, NSW, 1340 (Australia); Guizard, S.; Fedorov, N. [Laboratoire des Solides Irradies/CEA IRAMIS, Ecole Polytechnique, Palaiseau (France)

2011-12-15T23:59:59.000Z

458

Photovoltaic effect of a bilayer thin film with (Na0.5Bi0.5)1?xBaxTiO3/BiFeO3 heterostructure  

Science Journals Connector (OSTI)

A bilayer film containing (Na0.5Bi0.5)1?xBaxTiO3 (NBT–BT)/BiFeO3(BFO) heterostructure was produced by chemical solution deposition. An enhancement of photovoltaic performance of the bilayer film was discovered. It leads to a short circuit current density of 18.9 µA cm?2 and an open circuit voltage of 0.5 V, these values are much higher than that of BFO film. When transparent indium tin oxide (ITO) was used to substitute gold (Au) as top electrode, the photovoltaic voltage and photocurrent density, respectively, improved to ~0.71 V and ~45 µA cm?2. A theoretical band diagram model considering the ferroelectric polarization, heterostructure on the interface, and energy band bending effect was constructed to depict the mechanism of photovoltaic enhancement of the bilayer film. Temperature-dependent I–V measurements were carried out to explore the barrier height of the Au/BFO/NBT–BT/FTO heterostructure, and a total barrier height of 0.54 eV was obtained. Our work opens up a promising new method that has the potential for enhancing the photovoltaic performance for ferroelectric thin film, and provides deeper understanding of the photovoltaic mechanism of ferroelectric films.

Fen Wu; Yiping Guo; Bing Guo; Yangyang Zhang; Hua Li; Hezhou Liu

2013-01-01T23:59:59.000Z

459

Effect of co-doped SnO{sub 2} nanoparticles on photoluminescence of cu-doped potassium lithium borate glass  

SciTech Connect (OSTI)

The SnO{sub 2} co-doped lithium potassium borate glasses doped with 0.05, 0.10, 0.25 and 0.50 mol% of Cu were synthesized by the melt quenching technique. The SnO{sub 2} co-dope was added to the compounds in the amounts of 0.05, 0.10, and 0.20 mol%. The photoluminescent spectrum for different concentrations of copper was studied. It was observed that the intensity of blue emission (450, 490 nm) varies with concentration mol%. In addition, with different concentration of SnO{sub 2} to 0.10 mol% Cu, the influence of the luminescence has been observed to enhance intensity and shifted to blue and red (490, 535 nm) emissions.

Namma, Haydar Aboud; Wagiran, H.; Hussin, R.; Ariwahjoedi, B. [Department of Physics, Universiti Teknologi Malaysia, Skudai 81310, Malaysia and Baghdad College of Economic Sciences University (Iraq); Fundamental and Applied Sciences Department, Universiti Teknologi PETRONAS, 31750 Tronoh (Malaysia)

2012-09-26T23:59:59.000Z

460

B-Doped Graphene as Catalyst To Improve Charge Rate of Lithium–Air Battery  

Science Journals Connector (OSTI)

B-Doped Graphene as Catalyst To Improve Charge Rate of Lithium–Air Battery ... The lithium–air battery as an energy storage technology can be used in electric vehicles due to its large energy density, while its poor rate capability limits its practical usage under large current density. ... According to first-principles thermodynamics calculation, we predict B-doped graphene can be a potential catalyst to improve the charge rate of lithium–air battery. ...

Xiaodong Ren; Jinzhen Zhu; Fuming Du; Jianjun Liu; Wenqing Zhang

2014-09-10T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Supporting information for: Na-doped p-type ZnO , Faxian Xiu2  

E-Print Network [OSTI]

S1 Supporting information for: Na-doped p-type ZnO microwires Wei Liu1* , Faxian Xiu2 , Ke Sun1 flow was switched to argon followed by cooling to room temperature. After the growth, high-density Zn distribution of the Na Doped ZnO microwire 1.3 EDX line scans spectra #12;S3 Figure S3 a) a typical TEM image

Yang, Zheng

462

Controlling ferromagnetism of (In,Fe)As semiconductors by electron doping  

SciTech Connect (OSTI)

Based on experimental results, using the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) method and Monte Carlo simulation, we study the mechanism of ferromagnetic behavior of (In,Fe)As. We show that with doped Be atoms occupying in interstitial sites, chemical pair interactions between atoms and magnetic exchange interactions between Fe atoms change due to electron concentration. Therefore, by controlling the doping process, magnetic behavior of (In,Fe)As is controlled and ferromagnetism is observed in this semiconductor.

Dang Vu, Nguyen; Fukushima, Tetsuya; Katayama-Yoshida, Hiroshi [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan); Sato, Kazunori [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

2014-02-21T23:59:59.000Z

463

Structural and magnetic properties of self assembled Fe-doped Cu{sub 2}O nanorods  

SciTech Connect (OSTI)

Cuprous oxide (Cu{sub 2}O) nanorods doped with iron impurities have been synthesized by the polyol method using sodium dodecyl sulfate as the surfactant. The X-ray diffraction measurement reveals the pure phase of simple cubic Cu{sub 2}O and the electron microscopy displays its one dimensional morphology. Ferromagnetism was observed at room temperature in the magnetic measurements of the doped samples while undoped sample exhibits only diamagnetism. Room temperature Moessbauer spectra for the samples exhibited only doublets but no sextet, which corresponds to the presence of paramagnetic iron sites. As magnetic moment contribution of the doped ions was insignificant for the observed magnetism, ferromagnetic property in the doped samples could have been originated from the defects as cation vacancies. Existence of the defects was supported by the room temperature photoluminescence spectra of the doped samples in reference to the undoped sample. - Ferromagnetism at room temperature was observed in the Fe doped Cu{sub 2}O nanorods. The origin seems to be the defects of cation vacancies created by the dopant ions.

Ahmed, Asar [Department of Chemistry, SL-214, Southern Laboratory, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh (India); Gajbhiye, Namdeo S., E-mail: nsg@iitk.ac.i [Department of Chemistry, SL-214, Southern Laboratory, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh (India); Kurian, S. [Department of Chemistry, SL-214, Southern Laboratory, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh (India)

2010-09-15T23:59:59.000Z

464

Phosphorus and phosphorus nitrogen doped carbon nanotubes for ultrasensitive and selective molecular detection  

SciTech Connect (OSTI)

A first-principles approach is used to establish that substitutional phosphorus atoms within carbon nanotubes strongly modify the chemical properties of the surface, thus creating highly localized sites with specific affinity towards acceptor molecules. Phosphorus nitrogen co-dopants within the tubes have a similar effect for acceptor molecules, but the P N bond can also accept charge, resulting in affinity towards donor molecules. This molecular selectivity is illustrated in CO and NH3 adsorbed on PN-doped nanotubes, O2 on P-doped nanotubes, and NO2 and SO2 on both P- and PN-doped nanotubes. The adsorption of different chemical species onto the doped nanotubes modifies the dopant-induced localized states, which subsequently alter the electronic conductance. Although SO2 and CO adsorptions cause minor shifts in electronic conductance, NH3, NO2, and O2 adsorptions induce the suppression of a conductance dip. Conversely, the adsorption of NO2 on PN-doped nanotubes is accompanied with the appearance of an additional dip in conductance, correlated with a shift of the existing ones. Overall these changes in electric conductance provide an efficient way to detect selectively the presence of specific molecules. Additionally, the high oxidation potential of the P-doped nanotubes makes them good candidates for electrode materials in hydrogen fuel cells.

Cruz Silva, Eduardo [ORNL; Lopez, Florentino [IPICyT; Munoz-Sandoval, Emilio [IPICyT; Sumpter, Bobby G [ORNL; Terrones Maldonado, Humberto [ORNL; Charlier, Jean Christophe [Universite Catholique de Louvain; Meunier, Vincent [ORNL; Terrones Maldonado, Mauricio [ORNL

2011-01-01T23:59:59.000Z

465

P- and PN-Doped Nanotubes for Ultrasensitive and Selective Molecular Detection  

SciTech Connect (OSTI)

A first-principles approach is used to establish that substitutional phosphorus atoms strongly modify the chemical properties of the surface of carbon nanotubes, creating highly-localized sites with specific affinity towards acceptor molecules. Phosphorus-nitrogen co-dopants have a similar effect for acceptor molecules, but the P-N bond can also accept charge, resulting in affinity towards donor molecules. This molecular selectivity is illustrated in CO and NH3 adsorbed on PN doped nanotubes, O2 on P-doped nanotubes, and NO2 and SO2 on both P- and PN-doped nanotubes. The adsorption of different chemical species onto the doped nanotubes modifies the dopant-induced localized states, which subsequently alter electronic conductance. Although SO2 and CO adsorption cause minor shifts in electronic conductance; NH3, NO2, and O2 adsorptions induce the suppression of a conductance dip. Conversely, the adsorption of NO2 on PN-doped nanotubes is accompanied with the appearance of an additional dip in conductance, correlated with a shift of the existing ones. Overall these changes in electric conductance provide an efficient way to detect selectively the presence of specific molecules. Additionally, the high oxidation potential of the P-doped nanotubes makes them good candidates for electrode materials in hydrogen fuel cells.

Cruz Silva, Eduardo [ORNL; Terrones Maldonado, Humberto [ORNL; Terrones Maldonado, Mauricio [ORNL; Charlier, Jean Christophe [Universite Catholique de Louvain; Meunier, Vincent [ORNL; Sumpter, Bobby G [ORNL; Munoz-Sandoval, Emilio [IPICyT; Lopez, Florentino [IPICyT

2010-01-01T23:59:59.000Z

466

PHYSICAL REVIEW B 86, 075207 (2012) Optical signature of Mg-doped GaN: Transfer processes  

E-Print Network [OSTI]

results in the task of bipolar doping of intermediate and wide band-gap materials like CdS,1­3 ZnSe,4 ZnPHYSICAL REVIEW B 86, 075207 (2012) Optical signature of Mg-doped GaN: Transfer processes G; published 23 August 2012) Mg doping of high quality, metal organic chemical vapor deposition grown GaN films

Nabben, Reinhard

467

Unique Configuration of a Nitrogen-Doped Graphene Nanoribbon: Potential Applications to Semiconductor and Hydrogen Fuel Cell  

Science Journals Connector (OSTI)

Unique Configuration of a Nitrogen-Doped Graphene Nanoribbon: Potential Applications to Semiconductor and Hydrogen Fuel Cell ... Further examination on oxygen adsorption at NTSG reveals high electrocatalytic activity of NTSG in oxygen reduction reaction, indicating that this nitrogen-doped graphene material could be used as a potential catalyst for hydrogen fuel cells. ... (48) One recent theoretical work has also disclosed that the nitrogen-doped fullerene could be used as a potential catalyst for hydrogen fuel cells. ...

Hong Zheng; Jia-jia Zheng; Ling He; Xiang Zhao

2014-09-22T23:59:59.000Z

468

Fabrication of Chemically Doped, High Upper Critical Field Magnesium Diboride Superconducting Wires  

SciTech Connect (OSTI)

Controlled chemical doping of magnesium diboride (MgB2) has been shown to substantially improve its superconducting properties to the levels required for high field magnets, but the doping is difficult to accomplish through the usual route of solid state reaction and diffusion. Further, superconducting cables of MgB2 are difficult to fabricate because of the friable nature of the material. In this Phase I STTR project, doped and undoped boron fibers were made by chemical vapor deposition (CVD). Several >100m long batches of doped and undoped fiber were made by CVD codeposition of boron plus dopants. Bundles of these fibers infiltrated with liquid magnesium and subsequently converted to MgB2 to form Mg-MgB2 metal matrix composites. In a parallel path, doped boron nano-sized powder was produced by a plasma synthesis technique, reacted with magnesium to produce doped MgB2 superconducting ceramic bodies. The doped powder was also fabricated into superconducting wires several meters long. The doped boron fibers and powders made in this program were fabricated into fiber-metal composites and powder-metal composites by a liquid metal infiltration technique. The kinetics of the reaction between boron fiber and magnesium metal was investigated in fiber-metal composites. It was found that the presence of dopants had significantly slowed the reaction between magnesium and boron. The superconducting properties were measured for MgB2 fibers and MgB2 powders made by liquid metal infiltration. Properties of MgB2 products (Jc, Hc2) from Phase I are among the highest reported to date for MgB2 bulk superconductors. Chemically doped MgB2 superconducting magnets can perform at least as well as NbTi and NbSn3 in high magnetic fields and still offer an improvement over the latter two in terms of operating temperature. These characteristics make doped MgB2 an effective material for high magnetic field applications, such as magnetic confined fusion, and medical MRI devices. Developing fusion as an energy source will dramatically reduce energy costs, global warming, and radioactive waste. Cheaper and more efficient medical MRI devices could lower examination costs, find potential health problems earlier, and thus also benefit society as a whole. Other potential commercial applications for this material are devices for the generation and storage of electrical power, thus lowering the cost of delivered electricity.

Marzik, James, V.

2005-10-13T23:59:59.000Z

469

N-Doped Graphene–VO2(B) Nanosheet-Built 3D Flower Hybrid for Lithium Ion Battery  

Science Journals Connector (OSTI)

N-Doped Graphene–VO2(B) Nanosheet-Built 3D Flower Hybrid for Lithium Ion Battery ... Graphene-based electrode materials for rechargeable lithium batteries ...

C. Nethravathi; Catherine R. Rajamathi; Michael Rajamathi; Ujjal K. Gautam; Xi Wang; Dmitri Golberg; Yoshio Bando

2013-03-13T23:59:59.000Z

470

Room temperature ferromagnetism in magic-sized Cr-doped CdS diluted magnetic semiconducting quantum dots  

Science Journals Connector (OSTI)

Manipulation of carrier spins in semiconductors for spintronics applications has received great attention driven by improved functionalities and higher speed operation. Doping of semiconductor nanocrystals by tra...

Punita Srivastava; Pushpendra Kumar; Kedar Singh

2011-10-01T23:59:59.000Z

471

Fourier Transform Photothermal Deflection Spectroscopy of Impurity Centres in CdS Films: Doping and Annealing Effects  

Science Journals Connector (OSTI)

The subgap optical absorption of polycrystalline thin films was measured by Fourier Transform Photothermal Deflection Spectroscopy. Some impurity levels were identified : copper doping and annealing effects we...

M. Fathallah; B. Rezig; M. Zouaghi; N. M. Amer…

1988-01-01T23:59:59.000Z

472

Electrochemical properties of lithium polymer batteries with doped polyaniline as cathode material  

SciTech Connect (OSTI)

Graphical abstract: -- Abstract: Polyaniline (PANI) was doped with different lithium salts such as LiPF{sub 6} and LiClO{sub 4} and evaluated as cathode-active material for application in room-temperature lithium batteries. The doped PANI was characterized by FTIR and XPS measurements. In the FTIR spectra, the characteristic peaks of PANI are shifted to lower bands as a consequence of doping, and it is more shifted in the case of PANI doped with LiPF{sub 6}. The cathodes prepared using PANI doped with LiPF{sub 6} and LiClO{sub 4} delivered initial discharge capacities of 125 mAh g{sup ?1} and 112 mAh g{sup ?1} and stable reversible capacities of 114 mAh g{sup ?1} and 81 mAh g{sup ?1}, respectively, after 10 charge–discharge cycles. The cells were also tested using polymer electrolyte, which delivered highest discharge capacities of 142.6 mAh g{sup ?1} and 140 mAh g{sup ?1} and stable reversible capacities of 117 mAh g{sup ?1} and 122 mAh g{sup ?1} for PANI-LiPF{sub 6} and PANI-LiClO{sub 4}, respectively, after 10 cycles. The cathode prepared with LiPF{sub 6} doped PANI shows better cycling performance and stability as compared to the cathode prepared with LiClO{sub 4} doped PANI using both liquid and polymer electrolytes.

Manuel, James [Department of Chemical and Biological Engineering and Research Institute for Green Energy Convergence Technology, Gyeongsang National University, 900, Gajwa-dong, Jinju 660-701 (Korea, Republic of)] [Department of Chemical and Biological Engineering and Research Institute for Green Energy Convergence Technology, Gyeongsang National University, 900, Gajwa-dong, Jinju 660-701 (Korea, Republic of); Kim, Jae-Kwang; Matic, Aleksandar; Jacobsson, Per [Department of Applied Physics, Chalmers University of Technology, SE-41296 Göteborg (Sweden)] [Department of Applied Physics, Chalmers University of Technology, SE-41296 Göteborg (Sweden); Chauhan, Ghanshyam S. [Department of Chemistry, Himachal Pradesh University, Shimla 171005 (India)] [Department of Chemistry, Himachal Pradesh University, Shimla 171005 (India); Ha, Jong Keun; Cho, Kwon-Koo [Department of Materials Science and Engineering, Gyeongsang National University, 900, Gajwa-dong, Jinju 660-701 (Korea, Republic of)] [Department of Materials Science and Engineering, Gyeongsang National University, 900, Gajwa-dong, Jinju 660-701 (Korea, Republic of); Ahn, Jou-Hyeon, E-mail: jhahn@gnu.ac.kr [Department of Chemical and Biological Engineering and Research Institute for Green Energy Convergence Technology, Gyeongsang National University, 900, Gajwa-dong, Jinju 660-701 (Korea, Republic of)] [Department of Chemical and Biological Engineering and Research Institute for Green Energy Convergence Technology, Gyeongsang National University, 900, Gajwa-dong, Jinju 660-701 (Korea, Republic of)

2012-10-15T23:59:59.000Z

473

Laser ablation of silicate glasses doped with transuranic actinides  

SciTech Connect (OSTI)

Direct sampling laser ablation plasma mass spectrometry (DS-LAMS) was applied to silica glasses doped with {sup 237}Np, {sup 242}Pu or {sup 241}Am using a unique instrument recently installed into a transuranic glovebox. The primary goal was to assess the utility of mass spectrometry of directly ablated ions for facile evaluation of actinide (An) constituents of silicate glass immobilization matrices used for encapsulation of radionuclides. The instrument and general procedures have been described elsewhere. Three high-purity silicate glasses prepared by a sol-gel process (SG) and one conventional high-temperature (HT; melting point {approx} 1,450 C) borosilicate glass were studied. These glasses comprised the following constituents, with compositions expressed in mass percentages: Np-HT {approx} 30% SiO{sub 2} + 6% B{sub 2}O{sub 3} + 3% BaO + 13% Al{sub 2}O{sub 3} + 10% PbO + 30% La{sub 2}O{sub 3} + 8% {sup 237}NpO{sub 2}; Np-SG {approx} 70% SiO{sub 2} + 30% {sup 237}NpO{sub 2}; Pu-SG {approx} 70% SiO{sub 2} + 30% {sup 242}PuO{sub 2}; Am-SG {approx} 85% SiO{sub 2} + 15% {sup 241}AmO{sub 2}.

Gibson, J.K.; Haire, R.G.

1998-10-01T23:59:59.000Z

474

Impurity-doped optical shock, detonation and damage location sensor  

DOE Patents [OSTI]

A shock, detonation, and damage location sensor providing continuous fiber-optic means of measuring shock speed and damage location, and could be designed through proper cabling to have virtually any desired crush pressure. The sensor has one or a plurality of parallel multimode optical fibers, or a singlemode fiber core, surrounded by an elongated cladding, doped along their entire length with impurities to fluoresce in response to light at a different wavelength entering one end of the fiber(s). The length of a fiber would be continuously shorted as it is progressively destroyed by a shock wave traveling parallel to its axis. The resulting backscattered and shifted light would eventually enter a detector and be converted into a proportional electrical signals which would be evaluated to determine shock velocity and damage location. The corresponding reduction in output, because of the shortening of the optical fibers, is used as it is received to determine the velocity and position of the shock front as a function of time. As a damage location sensor the sensor fiber cracks along with the structure to which it is mounted. The size of the resulting drop in detector output is indicative of the location of the crack.

Weiss, Jonathan D. (Albuquerque, NM)

1995-01-01T23:59:59.000Z

475

Impurity-doped optical shock, detonation and damage location sensor  

DOE Patents [OSTI]

A shock, detonation, and damage location sensor providing continuous fiber-optic means of measuring shock speed and damage location, and could be designed through proper cabling to have virtually any desired crush pressure. The sensor has one or a plurality of parallel multimode optical fibers, or a singlemode fiber core, surrounded by an elongated cladding, doped along their entire length with impurities to fluoresce in response to light at a different wavelength entering one end of the fiber(s). The length of a fiber would be continuously shorted as it is progressively destroyed by a shock wave traveling parallel to its axis. The resulting backscattered and shifted light would eventually enter a detector and be converted into a proportional electrical signals which would be evaluated to determine shock velocity and damage location. The corresponding reduction in output, because of the shortening of the optical fibers, is used as it is received to determine the velocity and position of the shock front as a function of time. As a damage location sensor the sensor fiber cracks along with the structure to which it is mounted. The size of the resulting drop in detector output is indicative of the location of the crack. 8 figs.

Weiss, J.D.

1995-02-07T23:59:59.000Z

476

Study of Radioactive Impurities in Neutron Transmutation Doped Germanium  

E-Print Network [OSTI]

A program to develop low temperature (mK) sensors with neutron transmutation doped Ge for rare event studies with a cryogenic bolometer has been initiated. For this purpose, semiconductor grade Ge wafers are irradiated with thermal neutron flux from Dhruva reactor at BARC, Mumbai. Spectroscopic studies of irradiated samples have revealed that the environment of the capsule used for irradiating the sample leads to significant levels of $^{65}$Zn, $^{110}$Ag and $^{182}$Ta impurities, which can be reduced by chemical etching of approximately $\\sim50 \\mu$m thick surface layer. From measurements of the etched samples in the low background counting setup, activity due to trace impurities of $^{123}$Sb in bulk Ge is estimated to be $\\sim$ 1 Bq/gm after irradiation. These estimates indicate that in order to use the NTD Ge sensors for rare event studies, a cool down period of $\\sim$ 2 years would be necessary to reduce the radioactive background to $\\le$ 1 mBq/gm.

S. Mathimalar; N. Dokania; V. Singh; V. Nanal; R. G. Pillay; A. Shrivastava; K. C. Jagadeesan; S. V. Thakare

2014-11-27T23:59:59.000Z

477

DEVELOPMENT OF DOPED NANOPOROUS CARBONS FOR HYDROGEN STORAGE  

SciTech Connect (OSTI)

Hydrogen storage materials based on the hydrogen spillover mechanism onto metal-doped nanoporous carbons are studied, in an effort to develop materials that store appreciable hydrogen at ambient temperatures and moderate pressures. We demonstrate that oxidation of the carbon surface can significantly increase the hydrogen uptake of these materials, primarily at low pressure. Trace water present in the system plays a role in the development of active sites, and may further be used as a strategy to increase uptake. Increased surface density of oxygen groups led to a significant enhancement of hydrogen spillover at pressures less than 100 milibar. At 300K, the hydrogen uptake was up to 1.1 wt. % at 100 mbar and increased to 1.4 wt. % at 20 bar. However, only 0.4 wt% of this was desorbable via a pressure reduction at room temperature, and the high lowpressure hydrogen uptake was found only when trace water was present during pretreatment. Although far from DOE hydrogen storage targets, storage at ambient temperature has significant practical advantages oner cryogenic physical adsorbents. The role of trace water in surface modification has significant implications for reproducibility in the field. High-pressure in situ characterization of ideal carbon surfaces in hydrogen suggests re-hybridization is not likely under conditions of practical interest. Advanced characterization is used to probe carbon-hydrogen-metal interactions in a number of systems and new carbon materials have been developed.

Angela D. Lueking; Qixiu Li; John V. Badding; Dania Fonseca; Humerto Gutierrez; Apurba Sakti; Kofi Adu; Michael Schimmel

2010-03-31T23:59:59.000Z

478

Microwave sintering of pure and doped nanocrystalline alumina compacts  

SciTech Connect (OSTI)

A single-mode cavity microwave furnace, operating in the TE{sub 103} mode at 2.45 GHz is being used to investigate sintering of pure and doped nanocrystalline alumina. The purpose of these experiments is to determine the effect of additives on the sintering process in the nanocrystalline regime. Using the sol-gel method, high purity Al{sub 2}O{sub 3} nanocrystalline powders were synthesized. These powders were calcined at 700 C and then CIP`ed to 414 MPa, producing 0.4 in. diameter, 0.25 in. high cylindrical compacts. The compacts were heated in the microwave furnace to temperatures between 1,100 C to approximately 1,800 C and were then brought back to room temperature using a triangular heating profile of about 30 minutes duration. A two-color IR pyrometer was used to monitor the surface temperature of the workpiece. The additives tested in this work lowered the temperature needed for densification but this effect was offset by increased grain growth. Initial grain growth from <5 nm to {approximately}50 nm was closely correlated with the {gamma} to {alpha}-alumina phase transition.

Bruce, R.W. [SFA, Inc., Largo, MD (United States); Fliflet, A.W.; Lewis, D. III; Rayne, R.J.; Bender, B.A.; Chow, G.M.; Schoen, P.E. [Naval Research Lab., Washington, DC (United States); Kurihara, L.K. [Georgetown Univ., Washington, DC (United States). Dept. of Biochemistry

1996-12-31T23:59:59.000Z

479

Studies on lithium acetate doped chitosan conducting polymer system  

Science Journals Connector (OSTI)

The structure of chitosan contains the amine group that can act as electron donors. Complexation between chitosan and the salt can be proven by infrared and X-ray photoelectron spectroscopy methods. The NH2, NH3+ and O?C-NHR vibrations which can be observed at 1590, 1560 and 1650 cm?1 shift to lower wave numbers when the complexes are formed. The after deconvolution Li 1s core level spectrum of the chitosan–salt complexes can contain several gaussian components one of which has a binding energy peak at 55.2 eV which signifies Li–N interaction. The component that peaks at ?403 eV in the N 1s core level spectrum complements the proof of N–Li interaction. The highest conductivity achieved for a plasticized chitosan–salt complex is of the order 10?6 S/cm using lithium acetate as the doping salt. Transference number studies prove that this material is ionic conductor and from transient ionic current studies that mobility of the ions is of the order of 10?4 cm2/V s.

M.Z.A. Yahya; A.K. Arof

2002-01-01T23:59:59.000Z

480

Effect of Cr-doping on the structural and optical properties of CdS nanoparticles prepared by chemical precipitation method  

Science Journals Connector (OSTI)

Undoped and Cr doped CdS nanoparticles have been prepared by chemical precipitation ... diffraction analysis reveals that the undoped and Cr doped CdS nanoparticles exhibit hexagonal structure and the average ......

M. Thambidurai; N. Muthukumarasamy…

2012-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "doping dual-gated bilayer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Remarkable Strontium B-Site Occupancy in Ferroelectric Pb(Zr1-xTix)O3 Solid Solutions Doped with Cryolite-Type Strontium Niobate  

E-Print Network [OSTI]

Doped with Cryolite-Type Strontium Niobate” April 26, 2007Doped with Cryolite-Type Strontium Niobate” April 26, 2007and J. P. Loup, “Le Niobate de Strontium Sr 4 Nb 2 O 9 : Une

Feltz, A.; Schmidt-Winkel, P.; Schossman, M.; Booth, C.H.; Albering, J.

2007-01-01T23:59:59.000Z

482

Iodine doping effects on the lattice thermal conductivity of oxidized polyacetylene nanofibers  

SciTech Connect (OSTI)

Thermal transport in oxidized polyacetylene (PA) nanofibers with diameters in the range between 74 and 126?nm is measured with the use of a suspended micro heater device. With the error due to both radiation and contact thermal resistance corrected via a differential measurement procedure, the obtained thermal conductivity of oxidized PA nanofibers varies in the range between 0.84 and 1.24?W?m{sup ?1}?K{sup ?1} near room temperature, and decreases by 40%–70% after iodine doping. It is also found that the thermal conductivity of oxidized PA nanofibers increases with temperature between 100 and 350?K. Because of exposure to oxygen during sample preparation, the PA nanofibers are oxidized to be electrically insulating before and after iodine doping. The measurement results reveal that iodine doping can result in enhanced lattice disorder and reduced lattice thermal conductivity of PA nanofibers. If the oxidation issue can be addressed via further research to increase the electrical conductivity via doping, the observed suppressed lattice thermal conductivity in doped polymer nanofibers can be useful for the development of such conducting polymer nanostructures for thermoelectric energy conversion.

Bi, Kedong, E-mail: lishi@mail.utexas.edu, E-mail: kedongbi@seu.edu.cn [Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China); Department of Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712 (United States); Weathers, Annie; Pettes, Michael T.; Shi, Li, E-mail: lishi@mail.utexas.edu, E-mail: kedongbi@seu.edu.cn [Department of Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712 (United States); Matsushita, Satoshi; Akagi, Kazuo [Department of Polymer Chemistry, Kyoto University, Kyoto 615-8510 (Japan); Goh, Munju [Department of Polymer Chemistry, Kyoto University, Kyoto 615-8510 (Japan); Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Eunha-ri san 101, Bondong-eup, Wanju-gun, Jeolabuk-do 565-905 (Korea, Republic of)

2013-11-21T23:59:59.000Z

483

Doping profiles in CdTe/CdS thin film solar cells  

Science Journals Connector (OSTI)

CdS/CdTe thin film solar cells showing comparable properties as commercial cells have been prepared by close space sublimation (CSS) in our own laboratory. We characterised the cells by capacitance–voltage profiling (C–V), thermal admittance spectroscopy (TAS), and thermally stimulated capacitance measurements (TSCAP). The doping profiles of the CdTe layer obtained by C–V measurements confirm the well known rise in dopant concentration with increasing depth if the usual evaluation procedure is employed. However, the TAS and TSCAP measurements reveal deep acceptors in the CdTe layer with a large concentration exceeding that of the shallow dopants. Under these conditions, C–V measurements are shown to yield an apparently rising dopant concentration even for homogeneous doping. A combined simulation of doping profiles measured at different temperatures using a fixed and uniform shallow and deep doping fits well to measured doping concentration. These results indicate how to get reliable information on the shallow dopant concentration.

U. Reislöhner; M. Hädrich; N. Lorenz; H. Metzner; W. Witthuhn

2007-01-01T23:59:59.000Z

484

Nitrogen-doped graphene as transparent counter electrode for efficient dye-sensitized solar cells  

SciTech Connect (OSTI)

Graphical abstract: Display Omitted Highlights: ? NG sheets are prepared through a hydrothermal reduction of graphite oxide. ? The transparent NG counter electrodes of DSCs are fabricated at room temperature. ? Transparent NG electrode exhibits excellent catalytic activity for the reduction of I{sub 3}{sup ?}. ? The DSC with NG electrode achieves a comparable efficiency to that of the Pt-based cell. ? The efficiency of rear illumination is about 85% that of front illumination. -- Abstract: Nitrogen-doped graphene sheets are prepared through a hydrothermal reduction of graphite oxide in the presence of ammonia and applied to fabricate the transparent counter electrode of dye-sensitized solar cells. The atomic percentage of nitrogen in doped graphene sample is about 2.5%, and the nitrogen bonds display pyridine and pyrrole-like configurations. Cyclic voltammetry studies demonstrate a much higher electrocatalytic activity toward I{sup ?}/I{sub 3}{sup ?} redox reaction for nitrogen-doped graphene, as compared with pristine graphene. The dye-sensitized solar cell with this transparent nitrogen-doped graphene counter electrode shows conversion efficiencies of 6.12% and 5.23% corresponding to front-side and rear-side illumination, respectively. Meanwhile, the cell with a Pt counter electrode shows a conversion efficiency of 6.97% under the same experimental condition. These promising results highlight the potential application of nitrogen-doped graphene in cost-effective, transparent dye-sensitized solar cells.

Wang, Guiqiang, E-mail: wgqiang123@163.com [School of Chemical Engineering, Shandong University of Technology, Zibo 255049 (China)] [School of Chemical Engineering, Shandong University of Technology, Zibo 255049 (China); Fang, Yanyan; Lin, Yuan [Institute of Chemistry, Chinese Academy of Science, Beijing 100080 (China)] [Institute of Chemistry, Chinese Academy of Science, Beijing 100080 (China); Xing, Wei; Zhuo, Shuping [School of Chemical Engineering, Shandong University of Technology, Zibo 255049 (China)] [School of Chemical Engineering, Shandong University of Technology, Zibo 255049 (China)

2012-12-15T23:59:59.000Z

485

D{sup 0} magnetism in Ca doped narrow carbon nanotubes: First principle chirality effect study  

SciTech Connect (OSTI)

Curvature has always had crucial effects on the physical properties of narrow carbon nanotubes (CNTs) and here spin-polarized density functional calculations were employed to study electronic and magnetic properties of calcium-decorated narrow (5,5) and (9,0)CNTs with close diameters (?7?Å) and different chiralities. Our results showed that chirality had great impact on the electronic structure and magnetization of the doped CNTs. In addition, internally or externally doping of the calcium atoms was studied comparatively and although for the (9,0)CNT the internal doping was the most stable configuration, which involves a novel kind of spin-polarization originated from Ca-4s electrons, but for the (5,5)tube the external doping was the most stable one without any spin-polarization. On the other hand, calcium doping in the center of the (5,5)CNT was an endothermic process and led to the spin-polarization of unoccupied Ca-3d orbitals via direct exchange interaction between adjacent Ca atoms. In the considered systems, the existence of magnetization in the absence of any transition-metal elements was an example of valuable d{sup 0} magnetism title.

Hajiheidari, F.; Khoshnevisan, B., E-mail: b.khosh@kashanu.ac.ir [Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Hashemifar, S. J. [Faculty of Physics, Isfahan University of technology, 84156-83111 Isfahan (Iran, Islamic Republic of)

2014-06-21T23:59:59.000Z

486

Magnetic properties of transition metal doped AlN nanosheet: First-principle studies  

SciTech Connect (OSTI)

We carry out our first-principles calculations within density functional theory to study the 3d transition metal (TM) doped AlN nanosheets. The calculated results indicate that a stoichiometric AlN nanosheet is graphene-like structure and nonmagnetic. The TM impurities can induce magnetic moments, localized mainly on the 3d TM atoms and neighboring N atoms. Our calculated results of TM-doped nanosheet systems indicate a strong interaction between 3d orbit of TM atom and the 2p orbit of N atoms. In addition, the Mn- and Ni-doped AlN nanosheet with half-metal characters seems to be good candidates for spintronic applications. When substituting two Al atoms, the relative energies of the states between ferromagnetic and antiferromagnetic coupling are investigated sufficiently. The exchange coupling of Co- and Ni-doped AlN nanosheets exhibits a transformation with different distances of two TM atoms and that of Cr-, Mn-, and Fe-doped AlN nanosheets is not changed.

Shi, Changmin; Qin, Hongwei, E-mail: qin-hw@vip.163.com; Zhang, Yongjia; Hu, Jifan; Ju, Lin [School of Physics, State Key Laboratory for Crystal Materials, Shandong University, Jinan 250100 (China)

2014-02-07T23:59:59.000Z

487

Self-Doping, O2-Stable, n-Type Interfacial Layer for Organic Electronics  

SciTech Connect (OSTI)

Solid films of a water-soluble dicationic perylene diimide salt, perylene bis(2-ethyltrimethylammonium hydroxide imide), Petma{sup +}OH{sup -}, are strongly doped n-type by dehydration and reversibly de-doped by hydration. The hydrated films consist almost entirely of the neutral perylene diimide, PDI, while the dehydrated films contain {approx}50% PDI anions. The conductivity increases by five orders of magnitude upon dehydration, probably limited by film roughness, while the work function decreases by 0.74 V, consistent with an n-type doping density increase of {approx}12 orders of magnitude. Remarkably, the PDI anions are stable in dry air up to 120 C. The work function of the doped film, {phi} (3.96 V vs. vacuum), is unusually negative for an O{sub 2}-stable contact. Petma{sup +} OH{sup -} is also characterized as an interfacial layer, IFL, in two different types of organic photovoltaic cells. Results are comparable to state of the art cesium carbonate IFLs, but may improve if film morphology can be better controlled. The films are stable and reversible over many months in air and light. The mechanism of this unusual self-doping process may involve the change in relative potentials of the ions in the film caused by their deshielding and compaction as water is removed, leading to charge transfer when dry.

Reilly, T. H. III; Hains, A. W.; Chen, H. Y.; Gregg, B. A.

2012-04-01T23:59:59.000Z

488

Effect of the Doping Ion on the Electrical Response of a Free-Standing Polypyrrole Strip Subjected to Different Preloads  

E-Print Network [OSTI]

, a degeneration of the electrical energy vs the external stress was measured, which would seriously limit the useEffect of the Doping Ion on the Electrical Response of a Free-Standing Polypyrrole Strip Subjected they are immersed in aqueous solutions with different doping ions. By plotting the electrical energy associated

Otero, Toribio Fernández

489

CdS quantum dot sensitized nanocrystalline Gd-doped TiO2 thin films for photoelectrochemical solar cells  

Science Journals Connector (OSTI)

CdS quantum dot sensitized Gd-doped TiO2 nanocrystalline thin films have been prepared by chemical method. X-ray diffraction analysis reveals that TiO2 and Gd-doped TiO2...nanocrystalline thin films are of anatas...

A. Ranjitha; N. Muthukumarasamy…

2013-08-01T23:59:59.000Z

490

Cd doping effects in the heavy-fermion compounds Ce2MIn8 (M=Rh and Ir)  

Science Journals Connector (OSTI)

Low-temperature magnetic properties of Cd-doped Ce2MIn8 (M=Rh and Ir) single crystals are investigated. Experiments of temperature-dependent magnetic-susceptibility, heat-capacity, and electrical-resistivity measurements revealed that Cd doping enhances the antiferromagnetic (AFM) ordering temperature from TN=2.8?K (x=0) to TN=4.8?K (x=0.21) for Ce2RhIn8?xCdx and induces long-range AFM ordering with TN=3.8?K (x=0.21) for Ce2IrIn8?xCdx. Additionally, x-ray and neutron magnetic scattering studies showed that Cd-doped samples present below TN a commensurate antiferromagnetic structure with a propagation vector ??=(12,12,0). The resolved magnetic structures for both compounds indicate that the Cd doping tends to rotate the direction of the ordered magnetic moments toward the ab plane. This result suggests that the Cd doping affects the Ce3+ ground-state single-ion anisotropy modifying the crystalline electrical field (CEF) parameters at the Ce3+ site. Indications of CEF evolution induced by Cd doping were also found in the electrical-resistivity measurements. Comparisons between our results and the general effects of Cd doping on the related compounds CeMIn5 (M=Co, Rh, and Ir) confirms the claims that the Cd doping induced electronic tuning is the main effect favoring AFM ordering in these compounds.

C. Adriano; C. Giles; E. M. Bittar; L. N. Coelho; F. de Bergevin; C. Mazzoli; L. Paolasini; W. Ratcliff; R. Bindel; J. W. Lynn; Z. Fisk; P. G. Pagliuso

2010-06-15T23:59:59.000Z

491

Decorating anode with bamboo-like nitrogen-doped carbon nanotubes for microbial Suqin Ci a,c  

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Decorating anode with bamboo-like nitrogen-doped carbon nanotubes for microbial fuel cells Suqin Ci November 2011 Available online 20 November 2011 Keywords: Carbon nanotubes Nitrogen doping Anode Microbial. Introduction Microbial fuel cells (MFCs) are bio-electrochemical systems that directly convert chemical energy

492

Highmobility inverted selectively doped heterojunctions Hadas Shtrikman, M. Heiblum, K. Seo, D. E. Galbi, and L. Osterling  

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Highmobility inverted selectively doped heterojunctions Hadas Shtrikman, M. Heiblum, K. Seo, D. E in inverted GaAsAlGaAs heterojunctions Appl. Phys. Lett. 52, 1268 (1988); 10.1063/1.99176 High mobility: 132.76.50.6 On: Thu, 10 Apr 2014 16:05:40 #12;High-mobility inverted selectively doped heterojunctions

Heiblum, Mordehai "Moty"

493

Proton diffusion pathways and rates in Y-doped BaZrO3 solid oxide electrolyte from quantum mechanics  

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solid oxide fuel cells based on yttria-stabilized zirconia. In addition, doped perovskite oxides oftenProton diffusion pathways and rates in Y-doped BaZrO3 solid oxide electrolyte from quantum solid oxide proton conductors the principal fea- tures of the proton transport mechanism are generally

Goddard III, William A.

494

PHYSICAL REVIEW B 84, 205305 (2011) Spin-phonon coupling in single Mn-doped CdTe quantum dot  

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PHYSICAL REVIEW B 84, 205305 (2011) Spin-phonon coupling in single Mn-doped CdTe quantum dot C. L dynamics of a single Mn atom in a laser driven CdTe quantum dot is addressed theoretically. Recent of single Mn-doped CdTe dots, information about the quantum spin state of a single Mn atom is extracted from

Paris-Sud XI, Université de

495

Long-period fiber grating as wavelength selective element in double-clad Yb-doped fiber-ring lasers  

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Long-period fiber grating as wavelength selective element in double-clad Yb-doped fiber-ring lasers, 42.79.Dj, 42.81.-i 1. Introduction Cladding-pumped ytterbium-doped fiber lasers belong presently fiber laser with the cladding-pumped YDF a significant increase of the average output power can

Paris-Sud XI, Université de

496

Synthesis and Characterization of Ag-or Sb-Doped ZnO Nanorods by a Facile Hydrothermal Route  

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Synthesis and Characterization of Ag- or Sb-Doped ZnO Nanorods by a Facile Hydrothermal Route Oleg Stefan Cel Mare BouleVard, MD-2004 Chisinau, Republic of MoldoVa, AdVanced Materials Processing ZnO nanorods doped with Ag and Sb have been synthesized by a facile hydrothermal technique. Crystal

Kik, Pieter

497

Effect of microstructure, grain size, and rare earth doping on the electrorheological performance of nanosized particle materials  

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and grain sizes were prepared by doping TiO2 or ZrO2 with rare earth (RE) elements, and by changingEffect of microstructure, grain size, and rare earth doping on the electrorheological performance-Hua Zhang,c Shu-Mei Chen,d Rui-Li Huange and Song Gaoa a State Key Laboratory of Rare Earth Materials

Gao, Song

498

Hydrogen-doped cubic diamond and the crystal structure of n-diamond Bin Wen a,b,  

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Hydrogen-doped cubic diamond and the crystal structure of n-diamond Bin Wen a,b, , Roderick Melnik. In particular, hydrogen concen- tration dependent elastic constants and lattice parameters for the H-doped diamond have been analyzed. Our results indicate that when the hydrogen concentration is less than 19 at

Melnik, Roderick

499

Geometric and Electronic Properties of Sn-Doped TiO2 from First-Principles Calculations  

Science Journals Connector (OSTI)

Geometric and Electronic Properties of Sn-Doped TiO2 from First-Principles Calculations ... Finer k-point sets 3 × 3 × 4 and 3 × 5 × 4 were employed for calculating the electronic properties of doped rutile TiO2. ... This viewpoint is confirmed by the subsequent calculated formation energy. ...

Run Long; Ying Dai; Baibiao Huang

2008-12-17T23:59:59.000Z

500

Journal of Electronic Materials, Vol. 19, No, 4, 1990 Carbon Tetrachloride Doped AIxGa_xAS  

E-Print Network [OSTI]

Journal of Electronic Materials, Vol. 19, No, 4, 1990 Carbon Tetrachloride Doped AIx been shown to be a suitable carbon doping source for obtaining p-type GaAs grown by metalorganic chemical vapor deposition (MOCVD) with carbon acceptor concentrations in excess of 1 x 1019cm-3

Cunningham, Brian