Dynamic time expansion and compression using nonlinear waveguides
Findikoglu, Alp T. (Los Alamos, NM); Hahn, Sangkoo F. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)
2004-06-22T23:59:59.000Z
Dynamic time expansion or compression of a small-amplitude input signal generated with an initial scale is performed using a nonlinear waveguide. A nonlinear waveguide having a variable refractive index is connected to a bias voltage source having a bias signal amplitude that is large relative to the input signal to vary the reflective index and concomitant speed of propagation of the nonlinear waveguide and an electrical circuit for applying the small-amplitude signal and the large amplitude bias signal simultaneously to the nonlinear waveguide. The large amplitude bias signal with the input signal alters the speed of propagation of the small-amplitude signal with time in the nonlinear waveguide to expand or contract the initial time scale of the small-amplitude input signal.
Dynamic Time Expansion and Compression Using Nonlinear Waveguides
Findikoglu, Alp T.; Hahn, Sangkoo F.; Jia, Quanxi
2004-06-22T23:59:59.000Z
Dynamic time expansion or compression of a small amplitude input signal generated with an initial scale is performed using a nonlinear waveguide. A nonlinear waveguide having a variable refractive index is connected to a bias voltage source having a bias signal amplitude that is large relative to the input signal to vary the reflective index and concomitant speed of propagation of the nonlinear waveguide and an electrical circuit for applying the small amplitude signal and the large amplitude bias signal simultaneously to the nonlinear waveguide. The large amplitude bias signal with the input signal alters the speed of propagation of the small-amplitude signal with time in the nonlinear waveguide to expand or contract the initial time scale of the small-amplitude input signal.
Phase matching using Bragg reflection waveguides for monolithic nonlinear optics
, (2005). 9. P. Yeh, A. Yariv, " Bragg reflection waveguides," Opt. Commun. 19, 427-430 (1976). 10. P. Yeh, A. Yariv, C Hong "Electromagnetic propagation in periodic stratified media: I. General Theory," JPhase matching using Bragg reflection waveguides for monolithic nonlinear optics applications A. S
Nonlinear behavior of vibrating molecules on suspended graphene waveguides
Banerjee, Amrita
2015-01-01T23:59:59.000Z
Suspended graphene waveguides were deposited on micron-scale periodic metal (plasmonic) structures. Raman scattering of test molecules (B. Megaterium), deposited on the waveguides' surface, exhibited azimuthal cycles upon rotation: at these micron scales, spontaneous Raman ought to be independent of phase matching conditions. In addition, we observed angular-selective quadratic intensity dependence contrary to the typical linear behavior of spontaneous Raman. The effects were observed at very modest pump laser intensities (<10 MW/cm2 at the sample surface, oftenly used in Raman experiments). We attributed these observations to nonlinear coupling between the vibrating molecules and surface plasmon polariton (SPP) modes at the molecular vibration frequency. It was assessed that the polariton mode propagates through fairly long distances (over 100 microns).
Kazantseva, E V [Moscow Engineering Physics Institute (National Nuclear Research University), Moscow (Russian Federation); Maimistov, A I [Moscow Institute of Physics and Technology (State University), Dolgoprudnyi, Moscow Region (Russian Federation)
2013-09-30T23:59:59.000Z
Interaction of coupled waves propagating in a system of waveguides with alternating positive and negative refractive indices is studied theoretically. The zigzag configuration of the waveguides in the array allows communication not only between the nearest neighbours, but also with the waveguides beyond them. It is shown that the spectrum of linear waves in such a waveguide system has a bandgap. Partial solutions are found to the system of coupled waves corresponding to a stationary electromagnetic field pulse that propagates along the array of tunnel-coupled waveguides as a whole. Investigation of the interaction of nonlinear solitary waves has demonstrated numerically the stability of their relatively weak disturbances and collisions with each other. (nanogradient dielectric coatings and metamaterials)
Few-cycle self-compression via multimode nonlinear optics in gas filled waveguides
and spatial confinement of the pulse within the capillary, coupled with the relatively low gas pressuresFew-cycle self-compression via multimode nonlinear optics in gas filled waveguides P. N. Anderson1-compression of high energy ultrashort pulses within short gas filled capillaries. The mechanism observed allows
Arsenic Trisulfide on Lithium Niobate Waveguides for Nonlinear Infrared Optics
Chen, Qi
2014-08-04T23:59:59.000Z
Arsenic trisulfide (As_(2)S_(3)) waveguides on lithium niobate (LiNbO_(3)) substrate have a wide variety of applications in both near-infrared (near-IR) and mid-infrared (mid-IR). As an amorphous material, As_(2)S_(3) has ...
Title of dissertation: SEMICONDUCTOR WAVEGUIDES FOR NONLINEAR OPTICAL SIGNAL PROCESSING
Murphy, Thomas E.
the researchers and staff of cleanroom in LPS. Warren Berk, Dan Hinkel and Scott Horst have helped me a lot and Lisa Lucas have helped me for the general cleanroom training. I am also grateful to Prof. Gold- har and assistance for waveguide characterization. I would like to thank cleanroom staff of the Nanocenter
Quantum noise effects with Kerr nonlinearity enhancement in coupled gain-loss waveguides
Bing He; Shu-Bin Yan; Jing Wang; Min Xiao
2015-05-26T23:59:59.000Z
It is generally difficult to study the dynamical properties of a quantum system with both inherent quantum noises and non-perturbative nonlinearity. Due to the possibly drastic intensity increase of an input coherent light in the gain-loss waveguide couplers with parity-time (PT) symmetry, the Kerr effect from a nonlinearity added into the systems can be greatly enhanced, and is expected to create the macroscopic entangled states of the output light fields with huge photon numbers. Meanwhile, the quantum noises also coexist with the amplification and dissipation of the light fields. Under the interplay between the quantum noises and nonlinearity, the quantum dynamical behaviors of the systems become rather complicated. However, the important quantum noise effects have been mostly neglected in the previous studies about nonlinear PT-symmetric systems. Here we present a solution to this non-perturbative quantum nonlinear problem, showing the real-time evolution of the system observables. The enhanced Kerr nonlinearity is found to give rise to a previously unknown decoherence effect that is irrelevant to the quantum noises, and imposes a limit on the emergence of macroscopic nonclassicality. In contrast to what happen in the linear systems, the quantum noises exert significant impact on the system dynamics, and can create the nonclassical light field states in conjunction with the enhanced Kerr nonlinearity. This first study on the noise involved quantum nonlinear dynamics of the coupled gain-loss waveguides can help to better understand the quantum noise effects in the broad nonlinear systems.
Arsenic Trisulfide on Lithium Niobate Waveguides for Nonlinear Infrared Optics
Chen, Qi
2014-08-04T23:59:59.000Z
.................................................... 54 3.6.2 Analysis of InGaAs near-IR detector ........................................................ 56 3.6.3 Analysis of PbSe and MCT mid-IR detectors ............................................ 59 3.6.4 eSNR improvement...SNR enhancement compared to (a) PbSe; (b) MCT detectors .................. 62 Figure 4.1 Fabrication processes of As2S3-on-LiNbO3 waveguides .............................. 64 Figure 4.2 AJA magnetron sputtering system...
Saturable nonlinear dielectric waveguide with applications to broad-area semiconductor lasers
Mehuys, D.; Mittelstein, M.; Salzman, J.; Yariv, A.
1987-11-01T23:59:59.000Z
Self-focusing in a passive dielectric waveguide with a saturable nonlinearity is studied. The eigensolutions constitute a good approximation to the lateral modes of broad-area semiconductor lasers under low-duty-cycle pulsed conditions. The laser modes are predicted to consist of adjacent filaments coupled in phase, leading to a single-lobed far field, and to be stable with increased current injection above saturation intensity. The ultimate filament spacing is inversely proportional to the threshold gain, and thus wider filaments are expected in low-threshold broad-area lasers.
Lattice topology and spontaneous parametric down-conversion in quadratic nonlinear waveguide arrays
Leykam, Daniel; Sukhorukov, Andrey A; Desyatnikov, Anton S
2015-01-01T23:59:59.000Z
We analyze spontaneous parametric down-conversion in various experimentally feasible 1D quadratic nonlinear waveguide arrays, with emphasis on the relationship between the lattice's topological invariants and the biphoton correlations. Nontrivial topology results in a nontrivial "winding" of the array's Bloch waves, which introduces additional selection rules for the generation of biphotons. These selection rules are in addition to, and independent of existing control using the pump beam's spatial profile and phase matching conditions. In finite lattices, nontrivial topology produces single photon edge modes, resulting in "hybrid" biphoton edge modes, with one photon localized at the edge and the other propagating into the bulk. When the single photon band gap is sufficiently large, these hybrid biphoton modes reside in a band gap of the bulk biphoton Bloch wave spectrum. Numerical simulations support our analytical results.
Lattice topology and spontaneous parametric down-conversion in quadratic nonlinear waveguide arrays
Daniel Leykam; Alexander S. Solntsev; Andrey A. Sukhorukov; Anton S. Desyatnikov
2015-05-19T23:59:59.000Z
We analyze spontaneous parametric down-conversion in various experimentally feasible 1D quadratic nonlinear waveguide arrays, with emphasis on the relationship between the lattice's topological invariants and the biphoton correlations. Nontrivial topology results in a nontrivial "winding" of the array's Bloch waves, which introduces additional selection rules for the generation of biphotons. These selection rules are in addition to, and independent of existing control using the pump beam's spatial profile and phase matching conditions. In finite lattices, nontrivial topology produces single photon edge modes, resulting in "hybrid" biphoton edge modes, with one photon localized at the edge and the other propagating into the bulk. When the single photon band gap is sufficiently large, these hybrid biphoton modes reside in a band gap of the bulk biphoton Bloch wave spectrum. Numerical simulations support our analytical results.
Benjamin Brecht; Andreas Eckstein; Andreas Christ; Hubertus Suche; Christine Silberhorn
2011-07-28T23:59:59.000Z
Full control over the spatio-temporal structure of quantum states of light is an important goal in quantum optics, to generate for instance single-mode quantum pulses or to encode information on multiple modes, enhancing channel capacities. Quantum light pulses feature an inherent, rich spectral broadband-mode structure. In recent years, exploring the use of integrated optics as well as source-engineering has led to a deep understanding of the pulse-mode structure of guided quantum states of light. In addition, several groups have started to investigate the manipulation of quantum states by means of single-photon frequency conversion. In this paper we explore new routes towards complete control of the inherent pulse-modes of ultrafast pulsed quantum states by employing specifically designed nonlinear waveguides with adapted dispersion properties. Starting from our recently proposed quantum pulse gate (QPG) we further generalize the concept of spatio-spectral engineering for arbitrary $\\chitwo$-based quantum processes. We analyse the sum-frequency generation based QPG and introduce the difference-frequency generation based quantum pulse shaper (QPS). Together, these versatile and robust integrated optics devices allow for arbitrary manipulations of the pulse-mode structure of ultrafast pulsed quantum states. The QPG can be utilized to select an arbitrary pulse mode from a multimode input state, whereas the QPS enables the generation of specific pulse modes from an input wavepacket with Gaussian-shaped spectrum.
Chalcogenide-on-Lithium Niobate Resonator Waveguides and their nonlinear applications
Zhou, Yifeng
2014-12-03T23:59:59.000Z
-LiNbO3 optical waveguide platform and the resonant cavity structure together for the integrated all-optical circuits. A vertically integrated As2S3 ring resonator side-coupled to a low-index Ti:diffused LiNbO3 straight waveguide was designed...
Propagation of nonlinear waves in waveguides and application to nondestructive stress measurement
Nucera, Claudio
2012-01-01T23:59:59.000Z
Eval 56, 535-539. Rudenko, O.V. , 1993. Nonlinear Ekimov et al. , 1999; Rudenko, 1993; Zaitsev et al. ,
Guided wave methods and apparatus for nonlinear frequency generation
Durfee, III, Charles G. (Ann Arbor, MI); Rundquist, Andrew (Austin, TX); Kapteyn, Henry C. (Ann Arbor, MI); Murnane, Margaret M. (Ann Arbor, MI)
2000-01-01T23:59:59.000Z
Methods and apparatus are disclosed for the nonlinear generation of sum and difference frequencies of electromagnetic radiation propagating in a nonlinear material. A waveguide having a waveguide cavity contains the nonlinear material. Phase matching of the nonlinear generation is obtained by adjusting a waveguide propagation constant, the refractive index of the nonlinear material, or the waveguide mode in which the radiation propagates. Phase matching can be achieved even in isotropic nonlinear materials. A short-wavelength radiation source uses phase-matched nonlinear generation in a waveguide to produce high harmonics of a pulsed laser.
Al-Naffouri, Tareq Y.
A UNIFYING VIEW OF ERROR NONLINEARITIES IN LMS ADAPTATION Ta.req Y. Al-Na.ffouri Azzedine Zerguine of various error nonlinearities that are used in least mean square (LMS) adaptation such as the least mean that the LMS algorithm and its error- modified variants are approximations of two re- cently developed optimum
Diffraction control in periodically curved two-dimensional waveguide arrays
. Somekh, E. Garmire, A. Yariv, H. L. Garvin, and R. G. Hunsperger, "Channel optical waveguide directional, Alexander Szameit2, Andrey A. Sukhorukov1, Thomas Pertsch2, Wieslaw Krolikowski1, Stefan Nolte2, Dragomir, "Discretizing light behaviour in linear and nonlinear waveguide lattices," Nature 424, 817823 (2003). 2. A. L
Broad band waveguide spectrometer
Goldman, D.S.
1995-08-29T23:59:59.000Z
A spectrometer is disclosed for analyzing a sample of material utilizing a broad band source of electromagnetic radiation and a detector. The spectrometer employs a waveguide possessing an entry and an exit for the electromagnetic radiation emanating from the source. The waveguide further includes a surface between the entry and exit portions which permits interaction between the electromagnetic radiation passing through the waveguide and a sample material. A tapered portion forms a part of the entry of the waveguide and couples the electromagnetic radiation emanating from the source to the waveguide. The electromagnetic radiation passing from the exit of the waveguide is captured and directed to a detector for analysis. 16 figs.
Dispersion tailoring of the quarter-wave Bragg reflection waveguide
. Implications on nonlinear optical devices in compound semiconductors are discussed. ©2006 Optical Society., Handbook of Optical Components and Engineering (Wiley Interscience, 2003). 8. G. P. Agrawal, Nonlinear using semiconductor asymmetric coupled waveguides," J. Appl. Phys. 98, 113102 (2005). 11. M. A. Foster
Field renormalization in Photonic Crystal waveguides
Colman, P
2015-01-01T23:59:59.000Z
A novel strategy is introduced in order to include variations of the nonlinearity into the nonlinear schrodinger Equation. This technique, which relies on renormalization, is in particular well adapted to nanostructured optical systems where the nonlinearity exhibits large variations up to two orders of magnitude larger than in bulk material. We show that it takes into account in a simple and efficient way the specificity of the nonlinearity in nanostructures that is determined by geometrical parameters like the effective mode area and the group index. The renormalization of the nonlinear schrodinger Equation is the occasion for physics oriented considerations and unveils the potential of Photonic Crystal waveguides for the study of new nonlinear propagation phenomena.
Waveguide disturbance detection method
Korneev, Valeri A. (Albany, CA); Nihei, Kurt T. (Oakland, CA); Myer, Larry R. (Benicia, CA)
2000-01-01T23:59:59.000Z
A method for detection of a disturbance in a waveguide comprising transmitting a wavefield having symmetric and antisymmetric components from a horizontally and/or vertically polarized source and/or pressure source disposed symmetrically with respect to the longitudinal central axis of the waveguide at one end of the waveguide, recording the horizontal and/or vertical component or a pressure of the wavefield with a vertical array of receivers disposed at the opposite end of the waveguide, separating the wavenumber transform of the wavefield into the symmetric and antisymmetric components, integrating the symmetric and antisymmetric components over a broad frequency range, and comparing the magnitude of the symmetric components and the antisymmetric components to an expected magnitude for the symmetric components and the antisymmetric components for a waveguide of uniform thickness and properties thereby determining whether or not a disturbance is present inside the waveguide.
Broad band waveguide spectrometer
Goldman, Don S. (Folsom, CA)
1995-01-01T23:59:59.000Z
A spectrometer for analyzing a sample of material utilizing a broad band source of electromagnetic radiation and a detector. The spectrometer employs a waveguide possessing an entry and an exit for the electromagnetic radiation emanating from the source. The waveguide further includes a surface between the entry and exit portions which permits interaction between the electromagnetic radiation passing through the wave guide and a sample material. A tapered portion forms a part of the entry of the wave guide and couples the electromagnetic radiation emanating from the source to the waveguide. The electromagnetic radiation passing from the exit of the waveguide is captured and directed to a detector for analysis.
Levene, Michael J.; Korlach, Jonas; Turner, Stephen W.; Craighead, Harold G.; Webb, Watt W.
2007-02-20T23:59:59.000Z
The present invention is directed to a method and an apparatus for analysis of an analyte. The method involves providing a zero-mode waveguide which includes a cladding surrounding a core where the cladding is configured to preclude propagation of electromagnetic energy of a frequency less than a cutoff frequency longitudinally through the core of the zero-mode waveguide. The analyte is positioned in the core of the zero-mode waveguide and is then subjected, in the core of the zero-mode waveguide, to activating electromagnetic radiation of a frequency less than the cut-off frequency under conditions effective to permit analysis of the analyte in an effective observation volume which is more compact than if the analysis were carried out in the absence of the zero-mode waveguide.
Submicron optical waveguides and microring resonators fabricated by selective oxidation of
Fathpour, Sasan
@partow-tech.com Abstract: Submicron tantalum pentoxide ridge and channel optical waveguides and microring resonators, "Microring resonator channel dropping filters," J. Lightwave Technol. 15(6), 9981005 (1997). 5. D. Rafizadeh. Baumberg, "Determination of nonlinear refractive index in a Ta2O5 rib waveguide using self-phase modulation
Compound semiconductor optical waveguide switch
Spahn, Olga B.; Sullivan, Charles T.; Garcia, Ernest J.
2003-06-10T23:59:59.000Z
An optical waveguide switch is disclosed which is formed from III-V compound semiconductors and which has a moveable optical waveguide with a cantilevered portion that can be bent laterally by an integral electrostatic actuator to route an optical signal (i.e. light) between the moveable optical waveguide and one of a plurality of fixed optical waveguides. A plurality of optical waveguide switches can be formed on a common substrate and interconnected to form an optical switching network.
Surface modification to waveguides
Timberlake, J.R.; Ruzic, D.N.; Moore, R.L.; Cohen, S.A.; Manos, D.M.
1982-06-16T23:59:59.000Z
A method is described for treating the interior surfaces of a waveguide to improve power transmission comprising the steps of mechanically polishing to remove surface protrusions; electropolishing to remove embedded particles; ultrasonically cleaning to remove any residue; coating the interior waveguide surfaces with an alkyd resin solution or electrophoretically depositing carbon lamp black suspended in an alkyd resin solution to form a 1..mu.. to 5..mu.. thick film; vacuum pyrolyzing the film to form a uniform adherent carbon coating.
Nonlinear models Nonlinear Regression
Penny, Will
Nonlinear models Will Penny Nonlinear Regression Nonlinear Regression Priors Energies Posterior, UCL, March 2013 #12;Nonlinear models Will Penny Nonlinear Regression Nonlinear Regression Priors Example Sampling Metropolis-Hasting Proposal density References Nonlinear Regression We consider
Aqueous carrier waveguide in a flow cytometer
Mariella, Jr., Raymond P. (Danville, CA); van den Engh, Gerrit (Seattle, WA); Northrup, M. Allen (Berkeley, CA)
1995-01-01T23:59:59.000Z
The liquid of a flow cytometer itself acts as an optical waveguide, thus transmitting the light to an optical filter/detector combination. This alternative apparatus and method for detecting scattered light in a flow cytometer is provided by a device which views and detects the light trapped within the optical waveguide formed by the flow stream. A fiber optic or other light collecting device is positioned within the flow stream. This provides enormous advantages over the standard light collection technique which uses a microscope objective. The signal-to-noise ratio is greatly increased over that for right-angle-scattered light collected by a microscope objective, and the alignment requirements are simplified.
Aqueous carrier waveguide in a flow cytometer
Mariella, R.P. Jr.; Engh, G. van den; Northrup, M.A.
1995-12-12T23:59:59.000Z
The liquid of a flow cytometer itself acts as an optical waveguide, thus transmitting the light to an optical filter/detector combination. This alternative apparatus and method for detecting scattered light in a flow cytometer is provided by a device which views and detects the light trapped within the optical waveguide formed by the flow stream. A fiber optic or other light collecting device is positioned within the flow stream. This provides enormous advantages over the standard light collection technique which uses a microscope objective. The signal-to-noise ratio is greatly increased over that for right-angle-scattered light collected by a microscope objective, and the alignment requirements are simplified. 6 figs.
Cascaded third harmonic generation in hybrid graphene-semiconductor waveguides
Smirnova, Daria A
2015-01-01T23:59:59.000Z
We study cascaded harmonic generation of hybrid surface plasmons in integrated planar waveguides composed of a graphene layer and a doped-semiconductor slab. We derive a comprehensive model of cascaded third harmonic generation through phase-matched nonlinear interaction of fundamental, second harmonic and third harmonic plasmonic modes supported by the structure. We show that hybrid graphene-semiconductor waveguides can simultaneously phase-match these three interacting harmonics, increasing the total third-harmonic output by a factor of 5 compared to the non-cascaded regime.
Optical simulation of neutrino oscillations in binary waveguide arrays
Marini, Andrea; Biancalana, Fabio
2014-01-01T23:59:59.000Z
We theoretically propose and investigate an optical analogue of neutrino oscillations in a pair of vertically displaced binary waveguide arrays with longitudinally modulated effective refractive index. Optical propagation is modelled through coupled-mode equations, which in the continuous limit lead to two coupled Dirac equations for fermionic particles with different mass states, i.e. neutrinos. We demonstrate that neutrino oscillations can be quenched by nonlinear effects, and we predict the existence of neutrino solitons. Incidentally, these phenomena are expected to play an important role in massive supernova stars. Our results pave the way for using binary waveguide arrays as a classical laboratory for predicting exotic effects in particle physics and astrophysics.
Optical simulation of neutrino oscillations in binary waveguide arrays
Andrea Marini; Stefano Longhi; Fabio Biancalana
2014-05-06T23:59:59.000Z
We theoretically propose and investigate an optical analogue of neutrino oscillations in a pair of vertically displaced binary waveguide arrays with longitudinally modulated effective refractive index. Optical propagation is modelled through coupled-mode equations, which in the continuous limit lead to two coupled Dirac equations for fermionic particles with different mass states, i.e. neutrinos. We demonstrate that neutrino oscillations can be quenched by nonlinear effects, and we predict the existence of neutrino solitons. Incidentally, these phenomena are expected to play an important role in massive supernova stars. Our results pave the way for using binary waveguide arrays as a classical laboratory for predicting exotic effects in particle physics and astrophysics.
Influence of ponderomotive force on the microwave and plasma interaction in an elliptical waveguide
Abdoli-Arani, A., E-mail: abdoliabbas@kashanu.ac.ir [Department of Photonics, Faculty of Physics, University of Kashan, Kashan, Islamic Republic of Iran (Iran, Islamic Republic of)
2014-02-15T23:59:59.000Z
The interaction effect of a high-power microwave with the plasma in an elliptical waveguide taking into account the ponderomotive force is presented. Here, we assume the fundamental mode that propagates in an evacuated elliptical waveguide and encounters a plasma, which is filled in another elliptical waveguide of the same size. Here, we consider a balance between the effects of ponderomotive force and the electron pressure and consider the plasma effect through its dielectric permittivity because the electron density distribution of the plasma is modified. The propagation of the mode is described by two nonlinear coupled differential equations obtained using the Maxwell's equations. These equations are solved numerically using fourth order Runge-Kutta method for the field amplitude of the microwave in the waveguide considering the waveguide to be made up of a perfect conductor and filled with homogeneous plasma density distribution. The effects of the electron temperature, the microwave filed, and the frequency on the perturbed density profile are studied.
Active coupling control in densely packed subwavelength waveguides via dark mode
Suchowski, Haim; Hatakeyama, Taiki; Wu, Chihhui; Feng, Liang; OBrien, Kevin; Wang, Yuan; Zhang, Xiang
2015-01-01T23:59:59.000Z
The ever growing need for energy-efficient and fast communications is driving the development of highly integrated photonic circuits where controlling light at the nanoscale becomes the most critical aspect of information transfer . Directional couplers, two interacting optical waveguides placed in close proximity, are important building blocks in these integrated photonics circuits and have been employed as optical modulators and switches for high speed communication, data processing and integrated quantum operations. However, active control over the coupling between closely packed waveguides is highly desirable and yet remains a critical barrier towards ultra small footprint devices. A general approach to achieve active control in waveguide systems is to exploit optical nonlinearities enabled by a strong control pulse. However these devices suffer from the nonlinear absorption induced by the intense control pulse as the signal and its control propagate in the same waveguide. Here we experimentally demonstra...
Mode-Selective Optical Sensing using Asymmetric Waveguide Junctions
Racz, G. Zs.; Bamiedakis, N.; Penty, R.
2015-06-01T23:59:59.000Z
layer and the outer medium can be de-correlated. 3 Fig. 2. Schematic of the proposed optical waveguide sensor: (a) planar view and (b) top view, and cross section of the device at its different segments: (c) multimode input section, (d) sensing... derived with common linear algebra methods. 42 32 22 12 41 31 21 11 S S S S S S S S (5-6) 4. Simulation results In order to evaluate...
Ultrafast nonlinear optical properties of passive and active semiconductor devices
Motamedi, Ali Reza
2011-01-01T23:59:59.000Z
Nonlinear optical properties and ultrafast carrier dynamics of slab-coupled optical waveguide amplifiers, silicon nanowaveguides, and III-V semiconductor saturable Bragg reflectors are studied. The limits imposed by two ...
Scintillator Waveguide For Sensing Radiation
Bliss, Mary (West Richland, WA); Craig, Richard A. (West Richland, WA); Reeder; Paul L. (Richland, WA)
2003-04-22T23:59:59.000Z
The present invention is an apparatus for detecting ionizing radiation, having: a waveguide having a first end and a second end, the waveguide formed of a scintillator material wherein the therapeutic ionizing radiation isotropically generates scintillation light signals within the waveguide. This apparatus provides a measure of radiation dose. The apparatus may be modified to permit making a measure of location of radiation dose. Specifically, the scintillation material is segmented into a plurality of segments; and a connecting cable for each of the plurality of segments is used for conducting scintillation signals to a scintillation detector.
Single-shot fluctuations in waveguided high-harmonic generation
Goh, S J; van der Slot, P J M; Bastiaens, H J M; Herek, J; Biedron, S G; Danailov, M B; Milton, S V; Boller, K -J
2015-01-01T23:59:59.000Z
For exploring the application potential of coherent soft x-ray (SXR) and extreme ultraviolet radiation (XUV) provided by high-harmonic generation, it is important to characterize the central output parameters. Of specific importance are pulse-to-pulse (shot-to-shot) fluctuations of the high-harmonic output energy, fluctuations of the direction of the emission (pointing instabilities), and fluctuations of the beam divergence and shape that reduce the spatial coherence. We present the first single-shot measurements of waveguided high-harmonic generation in a waveguided (capillary-based) geometry. Using a capillary waveguide filled with Argon gas as the nonlinear medium, we provide the first characterization of shot-to-shot fluctuations of the pulse energy, of the divergence and of the beam pointing. We record the strength of these fluctuations vs. two basic input parameters, which are the drive laser pulse energy and the gas pressure in the capillary waveguide. In correlation measurements between single-shot dr...
Optical waveguides for microfluidic integration
Ram, Rajeev J.
A scalable polymer backplane for dense integration of photonics with lab-on-a-chip systems is presented. A high-throughput cell culture chip employing waveguides for monitoring and control of culture conditions is used to ...
Waveguides for performing enzymatic reactions
Levene; Michael J. (Ithaca, NY), Korlach; Jonas (Ithaca, NY), Turner; Stephen W. (Ithaca, NY), Craighead; Harold G. (Ithaca, NY), Webb; Watt W. (Ithaca, NY)
2007-11-06T23:59:59.000Z
The present invention is directed to a method and an apparatus for analysis of an analyte. The method involves providing a zero-mode waveguide which includes a cladding surrounding a core where the cladding is configured to preclude propagation of electromagnetic energy of a frequency less than a cutoff frequency longitudinally through the core of the zero-mode waveguide. The analyte is positioned in the core of the zero-mode waveguide and is then subjected, in the core of the zero-mode wave guide, to activating electromagnetic radiation of a frequency less than the cut-off frequency under conditions effective to permit analysis of the analyte in an effective observation volume which is more compact than if the analysis were carried out in the absence of the zero-mode waveguide.
High-energy ultrashort laser pulse compression in hollow planar waveguides
Boyer, Edmond
can be avoided by adjustment of the gas pressure. The spectral broadening is spatially uniform over by nonlinear propagation inside gas-filled planar hollow waveguides. We adjust the input beam size along can be achieved through pulse compression schemes such as gas- filled hollow core fibers [4
Vawter, G. Allen (Corrales, NM)
2008-02-26T23:59:59.000Z
A self-electrooptic effect device ("SEED") is integrated with waveguide interconnects through the use of vertical directional couplers. Light initially propagating in the interconnect waveguide is vertically coupled to the active waveguide layer of the SEED and, if the SEED is in the transparent state, the light is coupled back to the interconnect waveguide.
Optical panel system including stackable waveguides
DeSanto, Leonard (Dunkirk, MD); Veligdan, James T. (Manorville, NY)
2007-11-20T23:59:59.000Z
An optical panel system including stackable waveguides is provided. The optical panel system displays a projected light image and comprises a plurality of planar optical waveguides in a stacked state. The optical panel system further comprises a support system that aligns and supports the waveguides in the stacked state. In one embodiment, the support system comprises at least one rod, wherein each waveguide contains at least one hole, and wherein each rod is positioned through a corresponding hole in each waveguide. In another embodiment, the support system comprises at least two opposing edge structures having the waveguides positioned therebetween, wherein each opposing edge structure contains a mating surface, wherein opposite edges of each waveguide contain mating surfaces which are complementary to the mating surfaces of the opposing edge structures, and wherein each mating surface of the opposing edge structures engages a corresponding complementary mating surface of the opposite edges of each waveguide.
Non-degenerate two-photon absorption in silicon waveguides: Analytical and experimental study
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Zhang, Yanbing; Husko, Chad; Lefrancois, Simon; Rey, Isabella H.; Krauss, Thomas F.; Schröder, Jochen; Eggleton, Benjamin J.
2015-06-22T23:59:59.000Z
We theoretically and experimentally investigate the nonlinear evolution of two optical pulses in a silicon waveguide. We provide an analytic solution for the weak probe wave undergoing non-degenerate two-photon absorption (TPA) from the strong pump. At larger pump intensities, we employ a numerical solution to study the interplay between TPA and photo-generated free carriers. We develop a simple and powerful approach to extract and separate out the distinct loss contributions of TPA and free-carrier absorption from readily available experimental data. Our analysis accounts accurately for experimental results in silicon photonic crystal waveguides.
Enhanced four-wave mixing in graphene-silicon slow-light photonic crystal waveguides
Zhou, Hao, E-mail: hz2299@columbia.edu, E-mail: tg2342@columbia.edu, E-mail: cww2104@columbia.edu [College of Electronic Information, Sichuan University, Chengdu 610064 (China); Optical Nanostructures Laboratory, Columbia University, New York, New York 10027 (United States); Gu, Tingyi, E-mail: hz2299@columbia.edu, E-mail: tg2342@columbia.edu, E-mail: cww2104@columbia.edu; McMillan, James F.; Wong, Chee Wei, E-mail: hz2299@columbia.edu, E-mail: tg2342@columbia.edu, E-mail: cww2104@columbia.edu [Optical Nanostructures Laboratory, Columbia University, New York, New York 10027 (United States); Petrone, Nicholas; Zande, Arend van der; Hone, James C. [Mechanical Engineering, Columbia University, New York, New York 10027 (United States); Yu, Mingbin; Lo, Guoqiang; Kwong, Dim-Lee [The Institute of Microelectronics, Singapore 117685 (Singapore); Feng, Guoying [College of Electronic Information, Sichuan University, Chengdu 610064 (China); Zhou, Shouhuan [College of Electronic Information, Sichuan University, Chengdu 610064 (China); North China Research Institute of Electro-Optics, Beijing 100015 (China)
2014-09-01T23:59:59.000Z
We demonstrate the enhanced four-wave mixing of monolayer graphene on slow-light silicon photonic crystal waveguides. 200-?m interaction length, a four-wave mixing conversion efficiency of ?23?dB is achieved in the graphene-silicon slow-light hybrid, with an enhanced 3-dB conversion bandwidth of about 17?nm. Our measurements match well with nonlinear coupled-mode theory simulations based on the measured waveguide dispersion, and provide an effective way for all-optical signal processing in chip-scale integrated optics.
Ultracompact, broadband slot waveguide polarization splitter Shiyun Lin,1
-of-plane transverse directions. In con- ventional rib or channel waveguide configurations, however, the attainable-waveguide coupler for efficient channeling of the mixed-polarization light from an optical fiber to a single mode silicon channel waveguide, a directional coupler section where a slot waveguide and a channel waveguide
Analysis and optimization of a free-electron laser with an irregular waveguide
V. A. Goryashko
2010-04-08T23:59:59.000Z
Using a time-dependent approach the analysis and optimization of a planar FEL-amplifier with an axial magnetic field and an irregular waveguide is performed. By applying methods of nonlinear dynamics three-dimensional equations of motion and the excitation equation are partly integrated in an analytical way. As a result, a self-consistent reduced model of the FEL is built in special phase space. The reduced model is the generalization of the Colson-Bonifacio model and takes into account the intricate dynamics of electrons in the pump magnetic field and the intramode scattering in the irregular waveguide. The reduced model and concepts of evolutionary computation are used to find optimal waveguide profiles. The numerical simulation of the original non-simplified model is performed to check the effectiveness of found optimal profiles. The FEL parameters are chosen to be close to the parameters of the experiment (S. Cheng et al. IEEE Trans. Plasma Sci. 1996, vol. 24, p. 750), in which a sheet electron beam with the moderate thickness interacts with the TE01 mode of a rectangular waveguide. The results strongly indicate that one can improve the efficiency by a factor of five or six if the FEL operates in the magnetoresonance regime and if the irregular waveguide with the optimized profile is used.
Optical fiber having wave-guiding rings
Messerly, Michael J. (Danville, CA); Dawson, Jay W. (Livermore, CA); Beach, Raymond J. (Livermore, CA); Barty, Christopher P. J. (Hayward, CA)
2011-03-15T23:59:59.000Z
A waveguide includes a cladding region that has a refractive index that is substantially uniform and surrounds a wave-guiding region that has an average index that is close to the index of the cladding. The wave-guiding region also contains a thin ring or series of rings that have an index or indices that differ significantly from the index of the cladding. The ring or rings enable the structure to guide light.
Microwave gas breakdown in elliptical waveguides
Koufogiannis, I. D.; Sorolla, E., E-mail: eden.sorolla@epfl.ch; Mattes, M. [École Polytechnique Fédérale de Lausanne, Laboratoire d’Électromagnétisme et d'Acoustique (LEMA), Station 11, CH-1015 Lausanne (Switzerland)] [École Polytechnique Fédérale de Lausanne, Laboratoire d’Électromagnétisme et d'Acoustique (LEMA), Station 11, CH-1015 Lausanne (Switzerland)
2014-01-15T23:59:59.000Z
This paper analyzes the microwave gas discharge within elliptical waveguides excited by the fundamental mode. The Rayleigh-Ritz method has been applied to solve the continuity equation. The eigenvalue problem defined by the breakdown condition has been solved and the effective diffusion length of the elliptical waveguide has been calculated, what is used to find the corona threshold. This paper extends the microwave breakdown model developed for circular waveguides and shows the better corona withstanding capabilities of elliptical waveguides. The corona breakdown electric field threshold obtained with the variational method has been compared with the one calculated with the Finite Elements Method, showing excellent agreement.
Theory of Pulsed Four-Wave-Mixing in One-dimensional Silicon Photonic Crystal Slab Waveguides
Lavdas, Spyros
2015-01-01T23:59:59.000Z
We present a comprehensive theoretical analysis and computational study of four-wave mixing (FWM) of optical pulses co-propagating in one-dimensional silicon photonic crystal waveguides (Si-PhCWGs). Our theoretical analysis describes a very general set-up of the interacting optical pulses, namely we consider nondegenerate FWM in a configuration in which at each frequency there exists a superposition of guiding modes. We incorporate in our theoretical model all relevant linear optical effects, including waveguide loss, free-carrier (FC) dispersion and FC absorption, nonlinear optical effects such as self- and cross-phase modulation (SPM, XPM), two-photon absorption (TPA), and cross-absorption modulation (XAM), as well as the coupled dynamics of FCs and optical field. In particular, our theoretical analysis based on the coupled-mode theory provides rigorously derived formulae for linear dispersion coefficients of the guiding modes, linear coupling coefficients between these modes, as well as the nonlinear waveg...
Nonlinear Optics in Doped Silica Glass Integrated Waveguide Structures
Duchesne, David; Razzari, Luca; Morandotti, Roberto; Little, Brent; Chu, Sai T; Moss, David J
2015-01-01T23:59:59.000Z
Integrated photonic technologies are rapidly becoming an important and fundamental milestone for wideband optical telecommunications. Future optical networks have several critical requirements, including low energy consumption, high efficiency, greater bandwidth and flexibility, which must be addressed in a compact form factor.
Type-0 second order nonlinear interaction in monolithic waveguides of
of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4 biphoton source-property and preparation," Rep. Prog. Phys. 66, 1009 (2003). 2. C. K. Hong, Z. Y. Ou, and L
Zhang, Hao Chi; Guo, Jian; Fu, Xiaojian; Li, Lianming; Qian, Cheng; Cui, Tie Jun
2015-01-01T23:59:59.000Z
The second harmonic generation is one of the most important applications of nonlinear effect, which has attracted great interests in nonlinear optics and microwave in the past decades. To the best of our knowledge, however, generating the second harmonics of surface plasmon polaritons (SPPs) has not been reported. Here, we propose to generate the second harmonics of spoof SPPs with high efficiency at microwave frequencies using subwavelength-scale nonlinear active device integrated on specially designed plasmonic waveguides, which are composed of two ultrathin corrugated metallic strips printed on the top and bottom surfaces of a thin dielectric slab anti-symmetrically. We show that the plasmonic waveguide supports broadband propagations of spoof SPPs with strong subwavelength effect, whose dispersion property can be controlled by changing the geometrical parameters. By loading the nonlinear device made from semiconductors to the intersection of two plasmonic waveguides with different corrugation depths, we e...
Waveguide-based optical chemical sensor
Grace, Karen M. (Ranchos de Taos, NM); Swanson, Basil I. (Los Alamos, NM); Honkanen, Seppo (Tucson, AZ)
2007-03-13T23:59:59.000Z
The invention provides an apparatus and method for highly selective and sensitive chemical sensing. Two modes of laser light are transmitted through a waveguide, refracted by a thin film host reagent coating on the waveguide, and analyzed in a phase sensitive detector for changes in effective refractive index. Sensor specificity is based on the particular species selective thin films of host reagents which are attached to the surface of the planar optical waveguide. The thin film of host reagents refracts laser light at different refractive indices according to what species are forming inclusion complexes with the host reagents.
Method of making a scintillator waveguide
Bliss, Mary (West Richland, WA); Craig, Richard A. (West Richland, WA); Reeder, Paul L. (Richland, WA)
2000-01-01T23:59:59.000Z
The present invention is an apparatus for detecting ionizing radiation, having: a waveguide having a first end and a second end, the waveguide formed of a scintillator material wherein the therapeutic ionizing radiation isotropically generates scintillation light signals within the waveguide. This apparatus provides a measure of radiation dose. The apparatus may be modified to permit making a measure of location of radiation dose. Specifically, the scintillation material is segmented into a plurality of segments; and a connecting cable for each of the plurality of segments is used for conducting scintillation signals to a scintillation detector.
Waveguide device and method for making same
Forman, Michael A. (San Francisco, CA)
2007-08-14T23:59:59.000Z
A monolithic micromachined waveguide device or devices with low-loss, high-power handling, and near-optical frequency ranges is set forth. The waveguide and integrated devices are capable of transmitting near-optical frequencies due to optical-quality sidewall roughness. The device or devices are fabricated in parallel, may be mass produced using a LIGA manufacturing process, and may include a passive component such as a diplexer and/or an active capping layer capable of particularized signal processing of the waveforms propagated by the waveguide.
Dark solitons in dual-core waveguides with dispersive coupling
Kartashov, Yaroslav V; Malomed, Boris A
2015-01-01T23:59:59.000Z
We report on new types of two-component one-dimensional dark solitons (DSs) in a model of a dual-core waveguide with normal group-velocity dispersion and Kerr nonlinearity in both cores, the coupling between which is dispersive too. In the presence of the dispersive coupling, quiescent DSs supported by the zero-frequency background are always gray, being stable with the out-of-phase background, i.e., for opposite signs of the fields in the cores. On the contrary, the background with a nonzero frequency supports quiescent black solitons which may be stable for both out- and in-phase backgrounds, if the dispersive coupling is sufficiently strong. Only DSs supported by the out-of-phase background admit an extension to the case of nonzero phase mismatch between the cores.
Twisted waveguides for particle accelerator applications
Wilson, Joshua L.
A novel microwave device for accelerating charged particles based on twisted waveguide is presented. Twisted guides support slow-wave TM modes whose phase velocity could reach the speed of light c. The axial electric field ...
Multistaged stokes injected Raman capillary waveguide amplifier
Kurnit, Norman A. (Santa Fe, NM)
1980-01-01T23:59:59.000Z
A multistaged Stokes injected Raman capillary waveguide amplifier for providing a high gain Stokes output signal. The amplifier uses a plurality of optically coupled capillary waveguide amplifiers and one or more regenerative amplifiers to increase Stokes gain to a level sufficient for power amplification. Power amplification is provided by a multifocused Raman gain cell or a large diameter capillary waveguide. An external source of CO.sub.2 laser radiation can be injected into each of the capillary waveguide amplifier stages to increase Raman gain. Devices for injecting external sources of CO.sub.2 radiation include: dichroic mirrors, prisms, gratings and Ge Brewster plates. Alternatively, the CO.sub.2 input radiation to the first stage can be coupled and amplified between successive stages.
Spontaneous emission into a planar optical waveguide mode by an atom outside the waveguide
Andrei Modoran; Gregory Lafyatis
2006-09-18T23:59:59.000Z
An electronically excited atom or molecule located outside but near a planar optical waveguide can decay by spontaneous emission of a photon into a guided mode of the waveguide. We outline a QED theory for calculating the probability for this process and describe general physical insights from that theory. A couple of representative examples are discussed in detail.
Few-cycle dissipative solitons in active nonlinear optical fibres
Rosanov, N N; Semenov, V E; Vysotina, N V [Institute for Laser Physics, Federal State Unitary Enterprise ' Scientific and Industrial Corporation 'Vavilov State Optical Institute', St. Petersburg (Russian Federation)
2008-02-28T23:59:59.000Z
The propagation of self-induced transparency video pulses is studied in a waveguide containing two-level atoms of two types, which can either amplify or absorb pulses. It is shown that the amplified pulse can be compressed down to the duration comparable with the inverse frequency of the atomic transition (a few femtoseconds) along with the increase in the peak amplitude. The mechanisms restricting the compression of amplified self-induced transparency pulses are analysed (the introduction of the third atomic level and the use of the Bragg grating of the waveguide refractive index). (nonlinear optical phenomena)
Fabrication of Annealed Proton-Exchanged Waveguides for Vertical Integration
Webb, Jacob Douglas
2011-08-08T23:59:59.000Z
There is a drive for improving the surface uniformity of optical waveguide devices in the photonics lab. This report focuses on the exploration of annealed proton exchange (APE) waveguide fabrication on lithium niobate crystal as a method...
Integrated Low-Jitter 400-MHz Femtosecond Waveguide Laser
Shmulovich, J.
An integrated passively mode-locked waveguide laser generating 440-fs pulses at 394-MHz repetition rate is demonstrated on an 18 mm times 44 mm silica waveguide chip. The laser self-starts, and uses a saturable Bragg ...
A hybrid plasmonic waveguide terahertz quantum cascade laser
Degl'Innocenti, Riccardo; Shah, Yash D.; Wallis, Robert; Klimont, Adam; Ren, Yuan; Jessop, David S.; Beere, Harvey E.; Ritchie, David A.
2015-02-23T23:59:59.000Z
We present the realization of a quantum cascade laser emitting at around 2.85 terahertz, based on a hybrid plasmonic waveguide with a low refractive index dielectric cladding. This hybrid waveguide design allows the performance of a double...
Efficient power coupling to waveguides in high index contrast systems
Nguyen, Victor T. (Victor Trinh)
2006-01-01T23:59:59.000Z
Future integrated optical circuits will hold, on a single chip, several optical components that communicate via high index contrast waveguides. Silicon nitride (SixNy) and silicon oxynitride (SixOyNz) waveguides with silicon ...
Control of light diffusion in a disordered photonic waveguide
Sarma, Raktim; Cao, Hui, E-mail: hui.cao@yale.edu [Department of Applied Physics, Yale University, New Haven, Connecticut 06520 (United States); Golubev, Timofey; Yamilov, Alexey, E-mail: yamilov@mst.edu [Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409 (United States)
2014-07-28T23:59:59.000Z
We control the diffusion of light in a disordered photonic waveguide by modulating the waveguide geometry. In a single waveguide of varying cross-section, the diffusion coefficient changes spatially in two dimensions due to localization effects. The intensity distribution inside the waveguide agrees with the prediction of the self-consistent theory of localization. Our work shows that wave diffusion can be efficiently manipulated without modifying the structural disorder.
Waveguide-based Ultrasonic and Far-field Electromagnetic Sensors...
waveguide-based ultrasonic and farfield electromagnetic sensors to measure key Enhanced Geothermal Systems (EGS) reservoir parameters, including directional temperature,...
Characterization of bending loss in hollow flexible terahertz waveguides
Massachusetts at Lowell, University of
and metal/dielectric coated polycarbonate waveguides were investigated using an optically pumped far infrared (FIR) laser at 215 µm. The bending loss of silver coated polycarbonate waveguides were measured. Pedersen, and E. Mueller, "Hollow polycarbonate waveguides with inner Cu coatings for delivery of terahertz
AlGaAs-On-Insulator Nonlinear Photonics
Pu, Minhao; Semenova, Elizaveta; Yvind, Kresten
2015-01-01T23:59:59.000Z
The combination of nonlinear and integrated photonics has recently seen a surge with Kerr frequency comb generation in micro-resonators as the most significant achievement. Efficient nonlinear photonic chips have myriad applications including high speed optical signal processing, on-chip multi-wavelength lasers, metrology, molecular spectroscopy, and quantum information science. Aluminium gallium arsenide (AlGaAs) exhibits very high material nonlinearity and low nonlinear loss when operated below half its bandgap energy. However, difficulties in device processing and low device effective nonlinearity made Kerr frequency comb generation elusive. Here, we demonstrate AlGaAs-on-insulator as a nonlinear platform at telecom wavelengths. Using newly developed fabrication processes, we show high-quality-factor (Q>100,000) micro-resonators with integrated bus waveguides in a planar circuit where optical parametric oscillation is achieved with a record low threshold power of 3 mW and a frequency comb spanning 350 nm i...
Green's Function Formalism for Waveguide QED Applications
Schneider, Michael P; Stawiarski, Christina; Schmitteckert, Peter; Busch, Kurt
2015-01-01T23:59:59.000Z
We present a quantum-field-theoretical framework based on path integrals and Feynman diagrams for the investigation of the quantum-optical properties of one-dimensional waveguiding structures with embedded quantum impurities. In particular, we obtain the Green's functions for a waveguide with an embedded two-level system in the single- and two-excitation sector for arbitrary dispersion relations. In the single excitation sector, we show how to sum the diagrammatic perturbation series to all orders and thus obtain explicit expressions for physical quantities such as the spectral density and the scattering matrix. In the two-excitation sector, we show that strictly linear dispersion relations exhibit the special property that the corresponding diagrammatic perturbation series terminates after two terms, again allowing for closed-form expressions for physical quantities. In the case of general dispersion relations, notably those exhibiting a band edge or waveguide cut-off frequencies, the perturbation series can...
Integrated optical tamper sensor with planar waveguide
Carson, R.F.; Casalnuovo, S.A.
1993-01-05T23:59:59.000Z
A monolithic optical tamper sensor, comprising an optical emitter and detector, connected by an optical waveguide and placed into the critical entry plane of an enclosed sensitive region, the tamper sensor having a myriad of scraps of a material optically absorbent at the wavelength of interest, such that when the absorbent material is in place on the waveguide, an unique optical signature can be recorded, but when entry is attempted into the enclosed sensitive region, the scraps of absorbent material will be displaced and the optical/electrical signature of the tamper sensor will change and that change can be recorded.
Integrated optical tamper sensor with planar waveguide
Carson, Richard F. (Albuquerque, NM); Casalnuovo, Stephen A. (Albuquerque, NM)
1993-01-01T23:59:59.000Z
A monolithic optical tamper sensor, comprising an optical emitter and detector, connected by an optical waveguide and placed into the critical entry plane of an enclosed sensitive region, the tamper sensor having a myriad of scraps of a material optically absorbent at the wavelength of interest, such that when the absorbent material is in place on the waveguide, an unique optical signature can be recorded, but when entry is attempted into the enclosed sensitive region, the scraps of absorbent material will be displaced and the optical/electrical signature of the tamper sensor will change and that change can be recorded.
OPTICAL BIOPSY: COMPLEMENTING HISTOLOGY WITH NONLINEAR OPTICAL MICROSCOPY
Shafer, Christina
2006-08-16T23:59:59.000Z
Histology, though widely used for cellular imaging, suffers from its destructive nature; cells are not viewed in their natural living environment. Nonlinear optical microscopy (NLOM) has been widely used to view cells in situ without a need...
Mode imaging and loss evaluation of semiconductor waveguides
Mochizuki, Toshimitsu [Institute for Solid State Physics, The University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, Chiba (Japan); Fukushima Renewable Energy Institute, National Institute of Advanced Industrial Science and Technology, 2-2-9 Machiike-dai, Koriyama, Fukushima (Japan); Kim, Changsu; Yoshita, Masahiro; Nakamura, Takahiro; Akiyama, Hidefumi [Institute for Solid State Physics, The University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, Chiba (Japan); Pfeiffer, Loren N.; West, Ken W. [Department of Electrical Engineering, Princeton University, New Jersey 08544 (United States)
2014-05-15T23:59:59.000Z
An imaging and loss evaluation method for semiconductor waveguides coupled with non-doped quantum wells is presented. Using the internal emission of the wells as a probe light source, the numbers and widths of the modes of waveguides with various ridge sizes were evaluated by CCD imaging, and the obtained values were consistent with effective index method calculation. Waveguide internal losses were obtained from analyses of the Fabry-Pérot fringes of waveguide emission spectra. We quantified the quality of 29 single-mode waveguide samples as an internal loss and variation of 10.2 ± 0.6??cm{sup ?1}.
Compact waveguide power divider with multiple isolated outputs
Moeller, Charles P. (Del Mar, CA)
1987-01-01T23:59:59.000Z
A waveguide power divider (10) for splitting electromagnetic microwave power and directionally coupling the divided power includes an input waveguide (21) and reduced height output waveguides (23) interconnected by axial slots (22) and matched loads (25) and (26) positioned at the unused ends of input and output guides (21) and (23) respectively. The axial slots are of a length such that the wave in the input waveguide (21) is directionally coupled to the output waveguides (23). The widths of input guide (21) and output guides (23) are equal and the width of axial slots (22) is one half of the width of the input guide (21).
Analytical model for metalinsulatormetal mesh waveguide architectures
University in Cairo, New Cairo 11835, Egypt *Corresponding author: charleschihchin.lin@utoronto.ca Received X-junctions as power distribution elements to create interference and feedback effects, thereby- connects. With the majority of the optical power residing with- in the core, the waveguide is also highly
Dielectric waveguide gas-filled stark shift modulator
Hutchinson, Donald P.; Richards, Roger K.
2003-07-22T23:59:59.000Z
An optical modulator includes a dielectric waveguide for receiving an optical beam and coupling energy of the optical beam into the waveguide. At least one Stark material is provided in the waveguide. A bias circuit generates a bias signal to produce an electrical field across the Stark material to shift at least one of the Stark absorption frequencies towards the frequency of the optical beam. A circuit for producing a time varying electric field across the Stark material modulates the optical beam. At least a portion of the bias field can be generated by an alternating bias signal, such as a square wave. A method of modulating optical signals includes the steps of providing a dielectric waveguide for receiving an optical beam and coupling energy of the optical beam into the waveguide, the waveguide having at least one Stark material disposed therein, and varying an electric field imposed across the Stark material.
Molecular quantum wakes in the hydrodynamic plasma waveguide in air
Wu Jian; Cai Hua; Zeng Heping [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China); Milchberg, H. M. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States)
2010-10-15T23:59:59.000Z
We demonstrate a modulated plasma guiding effect from the molecular alignment wakes in the hydrodynamic plasma waveguide. A properly time-delayed laser pulse can be spatially confined by the hydrodynamic expansion induced plasma waveguide of an advancing femtosecond laser pulse. The spatial confinement can be further strengthened or weakened by following the quantum wakes of the impulsively excited rotational wave packets of the molecules in the plasma waveguide.
Waveguide-based Ultrasonic and Far-field Electromagnetic Sensors...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
waveguide-based ultrasonic and far- field electromagnetic sensors to measure key Enhanced Geothermal Systems (EGS) reservoir parameters, including directional temperature,...
Vector Network Analyzer Techniques to measure WR340 Waveguide...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
6 Vector Network Analyzer Techniques to Measure WR340 Waveguide Windows T. L. Smith ASD RF Group Advanced Photon Source Argonne National Laboratory June 26, 2002 Table of...
Multilayer Platform for Ultra-Low-Loss Waveguide Applications
2012-01-01T23:59:59.000Z
1, 2012 Multilayer Platform for Ultra-Low-Loss Waveguidepreviously demonstrated ultra-low-loss technologies. Groupet al. : MULTILAYER PLATFORM FOR ULTRA-LOW-LOSS WAVEGUIDE
Nonlinear Dynamics and Quantum Entanglement in Optomechanical Systems Guanglei Wang,1
Lai, Ying-Cheng
Nonlinear Dynamics and Quantum Entanglement in Optomechanical Systems Guanglei Wang,1 Liang Huang,2, is nonlinear. A nonlinear dynamical system can exhibit all kinds of interesting phenomena such as periodic at the other. In view of the ubiquity of nonlinear dynamics in physical systems and of the funda- mental
Integration of Arsenic Trisulfide and Titanium Diffused Lithium Niobate Waveguides
Solmaz, Mehmet E.
2011-08-08T23:59:59.000Z
A chalcogenide glass (arsenic-trisulfide, As2S3) optical waveguide is vertically integrated onto titanium-diffused lithium-niobate (Ti:LiNbO3) waveguides to add optical feedback paths and to create more compact optical circuits. Lithium...
Inverted-Rib Chalcogenide Waveguides by Solution Process Yunlai Zha,,
Arnold, Craig B.
Inverted-Rib Chalcogenide Waveguides by Solution Process Yunlai Zha,, Pao Tai Lin,,§ Lionel by a microtrench filling method. In this process, channels are etched on substrates and backfilled with solution for making reliable and low-loss arsenic sulfide waveguides based on a microtrench filling method. Channels
Modal Analysis of Homogeneous Optical Waveguides by Boundary Integral Method
Modal Analysis of Homogeneous Optical Waveguides by Boundary Integral Method Lei Wang J. Allen Cox of the waveguide. Two dierent systems of boundary integral equations are derived for the numerical solutions of the discrete propagation constants; one of them is in the form of Fredholm integral equations of the second
A lateral optical equilibrium in waveguide-resonator optical force
Fan, Shanhui
A lateral optical equilibrium in waveguide-resonator optical force Varat Intaraprasonk,1@stanford.edu Abstract: We consider the lateral optical force between a resonator and a waveguide, and study the possibility of an equilibrium that occurs solely from the optical force in such system. We prove analytically
Optical coupling between monocrystalline colloidal crystals and a planar waveguide
Avrutsky, Ivan
Optical coupling between monocrystalline colloidal crystals and a planar waveguide Y. Zhao,a) I demonstrated an optical material structure consisting of monocrystalline colloidal crystals and a planar struc- ture consisting of a planar waveguide and polycrystalline colloidal crystals.8 In this letter, we
Integration of Arsenic Trisulfide and Titanium Diffused Lithium Niobate Waveguides
Solmaz, Mehmet E.
2011-08-08T23:59:59.000Z
A chalcogenide glass (arsenic-trisulfide, As2S3) optical waveguide is vertically integrated onto titanium-diffused lithium-niobate (Ti:LiNbO3) waveguides to add optical feedback paths and to create more compact optical circuits. Lithium...
Waveguides for performing spectroscopy with confined effective observation volumes
Levene, Michael J.; Korlach, Jonas; Turner, Stephen W.; Craighead, Harold G.; Webb, Watt W.
2006-03-14T23:59:59.000Z
The present invention is directed to a method and an apparatus for analysis of an analyte. The method involves providing a zero-mode waveguide which includes a cladding surrounding a core where the cladding is configured to preclude propagation of electromagnetic energy of a frequency less than a cutoff frequency longitudinally through the core of the zero-mode waveguide. The analyte is positioned in the core of the zero-mode waveguide and is then subjected, in the core of the zero-mode waveguide, to activating electromagnetic radiation of a frequency less than the cut-off frequency under conditions effective to permit analysis of the analyte in an effective observation volume which is more compact than if the analysis were carried out in the absence of the zero-mode waveguide.
Combination ring cavity and backward Raman waveguide amplifier
Kurnit, Norman A. (Santa Fe, NM)
1983-01-01T23:59:59.000Z
A combination regenerative ring and backward Raman waveguide amplifier and a combination regenerative ring oscillator and backward Raman waveguide amplifier which produce Raman amplification, pulse compression, and efficient energy extraction from the CO.sub.2 laser pump signal for conversion into a Stokes radiation signal. The ring cavity configuration allows the CO.sub.2 laser pump signal and Stokes signal to copropagate through the Raman waveguide amplifier. The backward Raman waveguide amplifier configuration extracts a major portion of the remaining energy from the CO.sub.2 laser pump signal for conversion to Stokes radiation. Additionally, the backward Raman amplifier configuration produces a Stokes radiation signal which has a high intensity and a short duration. Adjustment of the position of overlap of the Stokes signal and the CO.sub.2 laser pump signal in the backward Raman waveguide amplifiers alters the amount of pulse compression which can be achieved.
La Rosa, Andres H.
Observation of coupled plasmon-polariton modes in Au nanoparticle chain waveguides of different corresponding to longitudinal (L) and transverse (T) plasmon-polariton modes of Au nanoparticle chains. Far noble metal nanoparticles.1 Energy transport in these plasmon waveguides relies on near-field coupling
Zhang, Xiaoshi (Superior, CO); Lytle, Amy L. (Boulder, CO); Cohen, Oren (Boulder, CO); Kapteyn, Henry C. (Boulder, CO); Murnane, Margaret M. (Boulder, CO)
2010-11-09T23:59:59.000Z
All-optical quasi-phase matching (QPM) uses a train of counterpropagating pulses to enhance high-order harmonic generation (HHG) in a hollow waveguide. A pump pulse enters one end of the waveguide, and causes HHG in the waveguide. The counterpropagation pulses enter the other end of the waveguide and interact with the pump pulses to cause QPM within the waveguide, enhancing the HHG.
Testing and Operation of the WR340 Waveguide Window in the APS Linac
Haase, Andrew
2003-08-11T23:59:59.000Z
The Advanced Photon Source (APS) linac high-power switching system makes extensive use of SF6 pressurized, WR340-size waveguide, incorporating waveguide switches. A tunable, extra low return loss waveguide window has been developed to support interfacing the pressurized waveguide with the original waveguide, which is under vacuum. The tunable approach is able to consistently achieve a return loss of at least 40 dB. Test and alignment methods, performance, and initial operating experience are described.
Testing and operation of the WR340 waveguide window in the APS linac.
Gerlick, A. E.; Berg, S.; Goeppner, G. A.; Nassiri, A.; Pile, G.; Smith, T. L.
2002-08-29T23:59:59.000Z
The Advanced Photon Source (APS) linac high-power switching system makes extensive use of SF6 pressurized, WR340-size waveguide, incorporating waveguide switches. A tunable, extra low return loss waveguide window has been developed to support interfacing the pressurized waveguide with the original waveguide, which is under vacuum. The tunable approach is able to consistently achieve a return loss of at least 40 dB. Test and alignment methods, performance, and initial operating experience are described.
Radio frequency (RF) microwave components and subsystems using loaded ridge waveguide
Kang, Yoon W.
2013-08-20T23:59:59.000Z
A waveguide having a non-conductive material with a high permeability (.mu., .mu..sub.r for relative permeability) and/or a high permittivity (.di-elect cons., .di-elect cons..sub.r for relative permittivity) positioned within a housing. When compared to a hollow waveguide, the waveguide of this invention, reduces waveguide dimensions by .varies..mu. ##EQU00001## The waveguide of this invention further includes ridges which further reduce the size and increases the usable frequency bandwidth.
Stokes injected Raman capillary waveguide amplifier
Kurnit, Norman A. (Santa Fe, NM)
1980-01-01T23:59:59.000Z
A device for producing stimulated Raman scattering of CO.sub.2 laser radiation by rotational states in a diatomic molecular gas utilizing a Stokes injection signal. The system utilizes a cryogenically cooled waveguide for extending focal interaction length. The waveguide, in conjunction with the Stokes injection signal, reduces required power density of the CO.sub.2 radiation below the breakdown threshold for the diatomic molecular gas. A Fresnel rhomb is employed to circularly polarize the Stokes injection signal and CO.sub.2 laser radiation in opposite circular directions. The device can be employed either as a regenerative oscillator utilizing optical cavity mirrors or as a single pass amplifier. Additionally, a plurality of Raman gain cells can be staged to increase output power magnitude. Also, in the regenerative oscillator embodiment, the Raman gain cell cavity length and CO.sub.2 cavity length can be matched to provide synchronism between mode locked CO.sub.2 pulses and pulses produced within the Raman gain cell.
Non-linearities in the quantum multiverse
Orfeu Bertolami; Victor Herdeiro
2012-08-01T23:59:59.000Z
It has been recently proposed that the multiverse of eternal inflation and the many-worlds interpretation of quantum mechanics can be identified, yielding a new view on the measure and measurement problems. In the present note, we argue that a non-linear evolution of observables in the quantum multiverse would be an obstacle for such a description and that these non-linearities are expected from quite general arguments.
Electromagnetic fields in nonuniform disk-loaded waveguides
Ayzatsky, M I
2015-01-01T23:59:59.000Z
On the base of general approach we obtain some results that can be useful in the process of tuning of nonunifrom disc-loaded waveguides. Our consideration has shown that simple values that characterize the detuning of the cells can be introduced only for the disc-loaded waveguide with parameters that change very slow. In general case it is needed to conduct full numerical simulation of specific disc-loaded waveguide and obtain all necessary coupling coefficients. After that one can start the tuning process on the base of bead-pull field distribution measurements.
Fourier Methods for Harmonic Scalar Waves in General Waveguides
Anders Andersson; Borje Nilsson; Thomas Biro
2015-06-01T23:59:59.000Z
A set of semi-analytical techniques based on Fourier analysis is used to solve wave scattering problems in variously shaped waveguides with varying normal admittance boundary conditions. Key components are newly developed conformal mapping methods, wave splitting, Fourier series expansions in eigen-functions to non-normal operators, the building block method or the cascade technique, Dirichlet-to-Neumann operators, and reformulation in terms of stable differential equations for reflection and transmission matrices. For an example the results show good correspondence with a finite element method solution to the same problem in the low and medium frequency domain. The Fourier method complements finite element analysis as a waveguide simulation tool. For inverse engineering involving tuning of straight waveguide parts joining complicated waveguide elements, the Fourier method is an attractive alternative including time aspects. The prime motivation for the Fourier method is its added physical understanding primarily at low frequencies.
Compact cladding-pumped planar waveguide amplifier and fabrication method
Bayramian, Andy J.; Beach, Raymond J.; Honea, Eric; Murray, James E.; Payne, Stephen A.
2003-10-28T23:59:59.000Z
A low-cost, high performance cladding-pumped planar waveguide amplifier and fabrication method, for deployment in metro and access networks. The waveguide amplifier has a compact monolithic slab architecture preferably formed by first sandwich bonding an erbium-doped core glass slab between two cladding glass slabs to form a multi-layer planar construction, and then slicing the construction into multiple unit constructions. Using lithographic techniques, a silver stripe is deposited and formed at a top or bottom surface of each unit construction and over a cross section of the bonds. By heating the unit construction in an oven and applying an electric field, the silver stripe is then ion diffused to increase the refractive indices of the core and cladding regions, with the diffusion region of the core forming a single mode waveguide, and the silver diffusion cladding region forming a second larger waveguide amenable to cladding pumping with broad area diodes.
Coupling efficiency of monolithic, waveguide-integrated Si photodetectors
Ahn, Donghwan
A waveguide-integrated photodetector provides a small-footprint, low-capacitance design that overcomes the bandwidth-efficiency trade-off problem of free space optics. High performance silicon devices are critical to the ...
Long-range hybrid ridge and trench plasmonic waveguides
Bian, Yusheng [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Gong, Qihuang, E-mail: qhgong@pku.edu.cn [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100871 (China)
2014-06-23T23:59:59.000Z
We report a class of long-range hybrid plasmon polariton waveguides capable of simultaneously achieving low propagation loss and tight field localization at telecommunication wavelength. The symmetric (quasi-symmetric) hybrid configurations featuring high-refractive-index-contrast near the non-uniform metallic nanostructures enable significantly improved optical performance over conventional hybrid waveguides, exhibiting considerably longer propagation distances and dramatically enhanced figure of merits for similar degrees of confinement. Compared to their traditional long-range plasmonic counterparts, the proposed hybrid waveguides put much less stringent requirements on index-matching conditions, demonstrating nice performance under a wide range of physical dimensions and robust characteristics against certain fabrication imperfections. Studies concerning crosstalk between adjacent identical waveguides further reveal their potential for photonic integrations. In addition, alternative configurations with comparable guiding properties to the structures in our case studies are also proposed, which can potentially serve as attractive prototypes for numerous high-performance nanophotonic components.
Angular output of hollow, metal-lined, waveguide Raman sensors
Biedrzycki, Stephen; Buric, Michael P.; Falk, Joel; Woodruff, Steven D.
2012-04-20T23:59:59.000Z
Hollow, metal-lined waveguides used as gas sensors based on spontaneous Raman scattering are capable of large angular collection. The collection of light from a large solid angle implies the collection of a large number of waveguide modes. An accurate estimation of the propagation losses for these modes is required to predict the total collected Raman power. We report a theory/experimental comparison of the Raman power collected as a function of the solid angle and waveguide length. New theoretical observations are compared with previous theory appropriate only for low-order modes. A cutback experiment is demonstrated to verify the validity of either theory. The angular distribution of Raman light is measured using aluminum and silver-lined waveguides of varying lengths.
Electromagnetic modeling of terahertz quantum cascade laser waveguides and resonators
Kohen, Stephen Michael, 1980-
2004-01-01T23:59:59.000Z
Finite-element numerical modeling and analysis of electromagnetic waveguides and resonators used in terahertz (THz) quantum cascade lasers (QCLs) is presented. Simulations and analysis of two types were performed: ...
Waveguide-integrated electroluminescent carbon nanotubes
Khasminskaya, Svetlana; Flavel, Benjamin S; Pernice, Wolfram H P; Krupke, Ralph
2013-01-01T23:59:59.000Z
Carbon based optoelectronic devices promise to revolutionize modern integrated circuits by combining outstanding electrical and optical properties into a unified technology. By coupling nanoelectronic devices to nanophotonic structures functional components such as nanoscale light emitting diodes, narrow-band thermal emitters, cavity controlled detectors and wideband electro optic modulators can be realized for chipscale information processing. These devices not only allow the light-matter interaction of low-dimensional systems to be studied, but also provide fundamental building blocks for high bandwidth on-chip communication. Here we demonstrate how light from an electrically-driven carbon-nanotube can be coupled directly into a photonic waveguide architecture. We realize wafer scale, broadband sources integrated with nanophotonic circuits allowing for propagation of light over centimeter distances. Moreover, we show that the spectral properties of the emitter can be controlled directly on chip with passive...
Popovic, Milos
2011-03-08T23:59:59.000Z
Low-loss waveguide structures may comprise a multimode waveguide supporting a periodic light intensity pattern, and attachments disposed at the waveguide adjacent low-intensity regions of the light intensity pattern.
Simulations of the spontaneous emission of a quantum dot near a gap plasmon waveguide
Perera, Chamanei S., E-mail: cp.hettiarachchige@qut.edu.au; Vernon, Kristy C.; Mcleod, Angus [Plasmonic Device Group, Queensland University of Technology, GPO box 2434, Brisbane, Queensland (Australia)
2014-02-07T23:59:59.000Z
In this paper, we modeled a quantum dot at near proximity to a gap plasmon waveguide to study the quantum dot-plasmon interactions. Assuming that the waveguide is single mode, this paper is concerned about the dependence of spontaneous emission rate of the quantum dot on waveguide dimensions such as width and height. We compare coupling efficiency of a gap waveguide with symmetric configuration and asymmetric configuration illustrating that symmetric waveguide has a better coupling efficiency to the quantum dot. We also demonstrate that optimally placed quantum dot near a symmetric waveguide with 50?nm?×?50?nm cross section can capture 80% of the spontaneous emission into a guided plasmon mode.
NONLINEAR OPTICS AT INTERFACES
Chen, Chenson K.
2010-01-01T23:59:59.000Z
N. Bloembergen, Nonlinear Optics (W. A. Benjamin, 1977) p.Research Division NONLINEAR OPTICS AT INTERFACES Chenson K.ED LBL-12084 NONLINEAR OPTICS AT INTERFACES Chenson K. Chen
Waveguide detection of right-angle-scattered light in flow cytometry
Mariella, Jr., Raymond P. (Danville, CA)
2000-01-01T23:59:59.000Z
A transparent flow cell is used as an index-guided optical waveguide. A detector for the flow cell but not the liquid stream detects the Right-Angle-Scattered (RAS) Light exiting from one end of the flow cell. The detector(s) could view the trapped RAS light from the flow cell either directly or through intermediate optical light guides. If the light exits one end of the flow cell, then the other end of the flow cell can be given a high-reflectivity coating to approximately double the amount of light collected. This system is more robust in its alignment than the traditional flow cytometry systems which use imaging optics, such as microscope objectives.
Evanescent Coupling Device Design for Waveguide-Integrated Group IV Photodetectors
Ahn, Donghwan
We have fabricated vertical p-i-n silicon photodetectors that are monolithically integrated with compact silicon-oxynitride channel waveguides. By comparing the evanescent coupling from low index-contrast waveguides and ...
Metal slit array Fresnel lens for wavelength-scale optical coupling to nanophotonic waveguides
Park, Namkyoo
Metal slit array Fresnel lens for wavelength-scale optical coupling to nanophotonic waveguides a novel metal slit array Fresnel lens for wavelength- scale optical coupling into a nanophotonic waveguide. Using the plasmonic waveguide structure in Fresnel lens form, a much wider beam acceptance angle
Plasmon-Waveguide Resonance Studies of Ligand Binding to the Human 2-Adrenergic Receptor
Kobilka, Brian
Plasmon-Waveguide Resonance Studies of Ligand Binding to the Human 2-Adrenergic Receptor SavithaVed October 8, 2003; ReVised Manuscript ReceiVed December 12, 2003 ABSTRACT: Plasmon-waveguide resonance (PWR activation in the 2-AR (7- 9). For the human -opioid receptor, plasmon-waveguide resonance (PWR) spectroscopy
Surface plasmon routing in dielectric-loaded surface plasmon polariton waveguides
Grandidier, Jonathan
Surface plasmon routing in dielectric-loaded surface plasmon polariton waveguides J. Grandidier, S ABSTRACT Waveguiding by dielectric-loaded surface plasmon-polaritons (DLSPP) structures are numerically waveguide parameters such as width and thickness on the properties of the surface plasmon guided modes
Sputtered TiN films for superconducting coplanar waveguide resonators S. Ohya,1, a)
Martinis, John M.
Sputtered TiN films for superconducting coplanar waveguide resonators S. Ohya,1, a) B. Chiaro,2 A control the energy of these particles to obtain high-quality TiN films. Superconducting coplanar waveguideN in larger circuits. I. INTRODUCTION Superconducting coplanar-waveguide (SCPW) res- onators are used
Observation of spontaneous Raman scattering in silicon slow-light photonic crystal waveguides
Hone, James
in silicon rib waveguides1 through the observations of amplification2 and finally to lasing.3,4 In addition to these achievements in rela- tively large mode area rib waveguides, the observation of spontaneous scattering5 and amplification6 has been made in submicron channel waveguides. In order to reduce the threshold power of Raman
Fabrication of metallic nano-slit waveguides with sharp bends.
Lu, M.; Ocola, L. E.; Gray, S. K.; Wiederrecht, G.; Center for Nanoscale Materials
2008-01-01T23:59:59.000Z
Metallic nanoslit waveguides are promising candidates for ultrahigh-density optical interconnections. A variety of devices based on metallic nanoslit waveguides have already been proposed that show a great superiority over conventional photonic devices for compactness. However very few two-dimensional devices have been experimentally demonstrated with in-plane geometries due to fabrication difficulties. In this article, a feasible process is presented using traditional semiconductor fabrication technologies such as mix-and-match lithography and electroplating, which is capable of fabricating complicated 100 nm wide, 800 nm deep gold slit waveguides with multiple sharp right-angle corners. The process can be extended to volume production manufacturing with minor modifications, thus enabling the fabrication of nanoslit photonic circuits and networks.
Model comparison for the density structure across solar coronal waveguides
Arregui, I; Ramos, A Asensio
2015-01-01T23:59:59.000Z
The spatial variation of physical quantities, such as the mass density, across solar atmospheric waveguides governs the timescales and spatial scales for wave damping and energy dissipation. The direct measurement of the spatial distribution of density, however, is difficult and indirect seismology inversion methods have been suggested as an alternative. We applied Bayesian inference, model comparison, and model-averaging techniques to the inference of the cross-field density structuring in solar magnetic waveguides using information on periods and damping times for resonantly damped magnetohydrodynamic (MHD) transverse kink oscillations. Three commonly employed alternative profiles were used to model the variation of the mass density across the waveguide boundary. Parameter inference enabled us to obtain information on physical quantities such as the Alfv\\'en travel time, the density contrast, and the transverse inhomogeneity length scale. The inference results from alternative density models were compared a...
Low loss, high and low index contrast waveguides in semiconductors
Bond, Tiziana (Livermore, CA); Cole, Garrett (Berkeley, CA); Goddard, Lynford (Champaign, IL); Kallman, Jeff (Pleasanton, CA)
2011-08-09T23:59:59.000Z
A system in one general embodiment includes a waveguide structure comprising a core of an alloy of Group III-V materials surrounded by an oxide (which may include one or more Group III-V metals), wherein an interface of the oxide and core is characterized by oxidation of the alloy for defining the core. A method in one general approach includes oxidizing a waveguide structure comprising an alloy of Group III-V materials for forming a core of the alloy surrounded by an oxide.
Ring cavity for a Raman capillary waveguide amplifier
Kurnit, N.A.
1981-01-27T23:59:59.000Z
A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.
Ring cavity for a Raman capillary waveguide amplifir
Kurnit, N.A.
1981-01-27T23:59:59.000Z
A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.
Ring cavity for a Raman capillary waveguide amplifier
Kurnit, N.A.
1983-07-19T23:59:59.000Z
Disclosed is a regenerative ring amplifier and regenerative ring oscillator which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO[sub 2] laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplifier Stokes signal is synchronous with the mode-locked spikes of the incoming CO[sub 2] laser pump signal. 6 figs.
Waveguide-integrated photonic crystal spectrometer with camera readout
Meng, Fan; Shiue, Ren-Jye; Li, Luozhou; Nie, Jing; Harris, Nicholas C.; Chen, Edward H.; Schröder, Tim; Englund, Dirk, E-mail: englund@mit.edu [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139 (United States); Wan, Noel [Department of Physics, Columbia University, New York, New York 10027 (United States); Pervez, Nadia [Chromation Partners LLC, 18 Bridge Street Suite 2J, Brooklyn, New York 11201 (United States); Kymissis, Ioannis [Chromation Partners LLC, 18 Bridge Street Suite 2J, Brooklyn, New York 11201 (United States); Department of Electrical Engineering, Columbia University, New York, New York 10027 (United States)
2014-08-04T23:59:59.000Z
We demonstrate an infrared spectrometer based on waveguide-coupled nanocavity filters in a planar photonic crystal structure. The input light is coupled into the waveguide, from which spectral components are dropped into the cavities and radiated off-chip for detection on a commercial InGaAs camera. The spectrometer has a footprint of only 60??m by 8??m. The spectral resolution is about 1?nm in the operation bandwidth of 1522–1545?nm. By substituting the membrane material and structure parameters, this design can be easily extended into the visible regime and developed for a variety of highly efficient, miniature photonic applications.
Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane
Texas at Austin, University of
Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane 1 Funded by Environmental. of Electrical and Computer Engineering, University of Texas, Austin #12;Motivation No other chip based optical Similar to: Doping of Semiconductor 3 #12;4 Photonic Crystal Bio-Chemical Sensors Loncar et al, Appl. Phys
High efficiency excitation of plasmonic waveguides with vertically integrated resonant
Xu, Xianfan
High efficiency excitation of plasmonic waveguides with vertically integrated resonant bowtie approach employs a bowtie aperture to provide both field confinement and high transmission efficiency. More than six times the power incident on the open area of the bowtie aperture can be coupled
Bragg reflection waveguides as integrated sources of entangled photon pairs
to design an electrically pumped entangled photon source. © 2012 Optical Society of America OCIS codes: 230Bragg reflection waveguides as integrated sources of entangled photon pairs Sergei V. Zhukovsky,1 of Physics and Institute for Optical Sciences, University of Toronto, 60 St. George Street, Toronto, Ontario
Comprehensive analysis of escape-cone losses from luminescent waveguides
Patrick, David L.
the need for solar tracking, the potential for achieving very large concentration factors, and deliv- ery of applications, from solar concentrators to doped fiber amplifiers. Here we report a comprehensive analysis the critical angle with a waveguide surface. For applications such as luminescent solar concentrators, escape
Silicon on ultra-low-loss waveguide photonic integration platform
Bauters, Jared; Davenport, Michael; Heck, Martijn; Doylend, Jonathan; Chen, Arnold; Fang, Alexander
2013-01-01T23:59:59.000Z
and J. E. Bowers, “Ultra-low-loss high-aspect-ratio Si 3 N 4and K. J. Vahala, “Ultra-low-loss optical delay line on aspiral is 78 mm long. 3. Ultra-low-loss waveguides with and
Shen, Y.R.
2010-01-01T23:59:59.000Z
B. de Castro, and Y. R. Shen, Optics Lett. i, 393 See, for3, 1980 SURFACE NONLINEAR OPTICS Y.R. Shen, C.K. Chen, andde Janiero SURFRACE NONLINEAR OPTICS Y. R. Shen, C. K. Chen,
57
2014-05-12T23:59:59.000Z
Journal of Nonlinear Science. The Principle of Hamilton for Mechanical Systems with Impacts and Unilateral. Constraints. --Manuscript Draft--. Manuscript ...
Propagation of nonlinear waves in waveguides and application to nondestructive stress measurement
Nucera, Claudio
2012-01-01T23:59:59.000Z
Techniques in Structural Health Monitoring. J Intel Mat process for Structural Health Monitoring Journal. Salamone,Workshop on Structural Health Monitoring (IWSHM), F-K.
Linear and nonlinear theory of cyclotron autoresonance masers with multiple waveguide modes
Wurtele, Jonathan
indicate that the saturated fractional rf power in a given mode reaches a maximum at its resonant magnetic) oscillators'-" and gyrotrons,4 mode competition de- termines the temporal behavior of the eigenmodes theory of multimode cyclotron resonance masers. Also, competition among abso- lutely unstable modes has
Propagation of nonlinear waves in waveguides and application to nondestructive stress measurement
Nucera, Claudio
2012-01-01T23:59:59.000Z
A.D. , 1975. Lateral buckling of railroad tracks Kerr, A.D. , 1978a. Lateral buckling or railroad tracks buckling collapse mechanisms characterized by sudden and rapid lateral
Ho, Y.-C.; Hung, T.-S.; Chen, W.-H. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China) [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Jhou, J.-G. [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China) [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Department of Physics, National Taiwan University, Taipei 106, Taiwan (China); Qayyum, H.; Chen, S.-Y. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China) [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Molecular Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 115, Taiwan (China); Chu, H.-H. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China)] [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Lin, J.-Y. [Department of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China)] [Department of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China); Wang, J. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China) [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Department of Physics, National Taiwan University, Taipei 106, Taiwan (China)
2013-08-15T23:59:59.000Z
By adding a transverse heater pulse into the axicon ignitor-heater scheme for producing a plasma waveguide, a variable three-dimensionally structured plasma waveguide can be fabricated. With this technique, electron injection in a plasma-waveguide-based laser wakefield accelerator was achieved and resulted in production of a quasi-monoenergetic electron beam. The injection was correlated with a section of expanding cross-section in the plasma waveguide. Moreover, the intensity of the X-ray beam produced by the electron bunch in betatron oscillation was greatly enhanced with a transversely shifted section in the plasma waveguide. The technique opens a route to a compact hard-X-ray pulse source.
Vertically-tapered optical waveguide and optical spot transformer formed therefrom
Bakke, Thor; Sullivan, Charles T.
2004-07-27T23:59:59.000Z
An optical waveguide is disclosed in which a section of the waveguide core is vertically tapered during formation by spin coating by controlling the width of an underlying mesa structure. The optical waveguide can be formed from spin-coatable materials such as polymers, sol-gels and spin-on glasses. The vertically-tapered waveguide section can be used to provide a vertical expansion of an optical mode of light within the optical waveguide. A laterally-tapered section can be added adjacent to the vertically-tapered section to provide for a lateral expansion of the optical mode, thereby forming an optical spot-size transformer for efficient coupling of light between the optical waveguide and a single-mode optical fiber. Such a spot-size transformer can also be added to a III-V semiconductor device by post processing.
Nanowire photonic crystal waveguides for single-atom trapping and strong light-matter interactions
Yu, S.-P.; Hood, J. D.; Muniz, J. A.; Martin, M. J.; Hung, C.-L.; Kimble, H. J., E-mail: hjkimble@caltech.edu [Norman Bridge Laboratory of Physics 12-33, California Institute of Technology, Pasadena, California 91125 (United States); Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Norte, Richard; Meenehan, Seán M.; Cohen, Justin D.; Painter, Oskar, E-mail: opainter@caltech.edu [Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Thomas J. Watson, Sr., Laboratory of Applied Physics 128-95, California Institute of Technology, Pasadena, California 91125 (United States)
2014-03-17T23:59:59.000Z
We present a comprehensive study of dispersion-engineered nanowire photonic crystal waveguides suitable for experiments in quantum optics and atomic physics with optically trapped atoms. Detailed design methodology and specifications are provided, as are the processing steps used to create silicon nitride waveguides of low optical loss in the near-IR. Measurements of the waveguide optical properties and power-handling capability are also presented.
Amplification from Nd3+ doped SiTi solgel channel waveguides
Arie, Ady
Amplification from Nd3+ doped SiTi solgel channel waveguides Asher Peled a,*, Menachem Nathan based on a Nd3+ doped solgel tapered rib waveguide. The solgel matrix composition is 50SiO2:50TiO2 into and out of the rib waveguide. A photoluminescence lifetime of 138 ls and a pump absorption cross
High power windows for WR650 waveguide couplers
Mircea Stirbet; Robert Rimmer; Thomas Elliott; Edward Daly; Katherine Wilson; Lynn Vogel; Haipeng Wang; Brian Carpenter; Karl Smith; Thomas Powers; Michael Drury; Robert Nichols; G. Davis
2007-06-01T23:59:59.000Z
Based on the robust, pre-stressed planar window concept successfully tested for PEP II and LEDA, a new design for planar ceramic windows to be used with WR650 waveguide fundamental power couplers at 1300 MHz or 1500 MHz has been developed. These windows should operate in pulsed or CW mode and sustain at least 100 kW average power levels. This paper describes an overview of the simulations performed to match the ceramics in WR650 waveguides, design details, as well as the RF measurements and performance assessed by RF power tests on several high power windows manufactured at JLAB. Funding Agency: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177, and by The Office of Naval Research under contract to the Dept. of Energy.
Method of fabricating optical waveguides by ion implantation doping
Appleton, B.R.; Ashley, P.R.; Buchal, C.J.
1987-03-24T23:59:59.000Z
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.
Hybrid plasmonic waveguide in a metal V-groove
Chen, Zhao-xian; Wu, Zi-jian; Ming, Yang; Zhang, Xue-jin, E-mail: xuejinzh@nju.edu.cn; Lu, Yan-qing, E-mail: yqlu@nju.edu.cn [National Laboratory of Solid State Microstructures and College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093 (China)] [National Laboratory of Solid State Microstructures and College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093 (China)
2014-01-15T23:59:59.000Z
We propose and investigate a type of hybrid plasmonic waveguide in a metal V-groove. A high-permittivity nanowire was placed in the metal channel covered with a dielectric film of lower permittivity. Deeper sub-wavelength confinement and much longer propagation distance were achieved in comparison with conventional channel plasmonic waveguides. The overall performance was improved as compared with the conventional hybrid plasmonic structure based on a flat metal surface. Finite element analysis showed that both the mode propagation and field profile can be adjusted by changing the nanowire radius and film thickness. Some benefits, such as a reduced scattering loss caused by the surface roughness, are also expected owing to the unique mode profile. The proposed approach has potential for application in high-level photonic integration.
Adiabatic and nonadiabatic nanofocusing of plasmons by tapered gap plasmon waveguides
Pile, DFP; Gramotnev, D K
2006-01-01T23:59:59.000Z
wave vector of the gap plasmon generated by a line sourcean adaptor between two gap plasmon waveguides of the widthslosses for the focused plasmons, because they have to
Calculations of modal characteristics of dielectric slab waveguides by a hybrid method
Wong, Eddie Tze-Chung
1985-01-01T23:59:59.000Z
) To transform Eq. (3 9) into a, variationa1 problem, the variation of g~(x), 6g~(z), is multiplied to Eq. (3. 9) and then integrated across the ent, ire thickness of the slab waveguide to obtain f OO d2 6g (z)( ? g (z)l ~ 6g?(x)~k ? k Ig (z)dz dzz rd d2... waveguide. 6. Arrangement of triangular basis functions 7. Field distribution in the guide region of a slab waveguide. 8. A slab waveguide (a) with graded index profile (b). 9. Approximation of an index profile by a series of step functions. 10. A...
Direct Scattering Processes and Signatures of Chaos in Quantum Waveguides
G. B. Akguc; L. E. Reichl
2003-02-14T23:59:59.000Z
The effect of direct processes on the statistical properties of deterministic scattering processes in a chaotic waveguide is examined. The single channel Poisson kernel describes well the distribution of S-matrix eigenphases when evaluated over an energy interval. When direct processes are transformed away, the scattering processes exhibit universal random matrix behavior. The effect of chaos on scattering wavefunctions,eigenphases, and time delays is discussed.
Target molecules detection by waveguiding in a photonic silicon membrane
Letant, Sonia E. (Livermore, CA); Van Buuren, Anthony (Livermore, CA); Terminello, Louis (Danville, CA); Hart, Bradley R. (Brentwood, CA)
2006-12-26T23:59:59.000Z
Disclosed herein is a porous silicon filter capable of binding and detecting biological and chemical target molecules in liquid or gas samples. A photonic waveguiding silicon filter with chemical and/or biological anchors covalently attached to the pore walls bind target molecules. The system uses transmission curve engineering principles to allow measurements to be made in situ and in real time to detect the presence of various target molecules and calculate the concentration of bound target.
Target molecules detection by waveguiding in a photonic silicon membrane
Letant, Sonia; Van Buuren, Anthony; Terminello, Louis
2004-08-31T23:59:59.000Z
Disclosed herein is a photonic silicon filter capable of binding and detecting biological and chemical target molecules in liquid or gas samples. A photonic waveguiding silicon filter with chemical and/or biological anchors covalently attached to the pore walls selectively bind target molecules. The system uses transmission curve engineering principles to allow measurements to be made in situ and in real time to detect the presence of various target molecules and determine the concentration of bound target.
Ultrafast Optical Switching Using Photonic Molecules in Photonic Crystal Waveguides
Zhao, Yanhui; Qiu, Kangsheng; Gao, Yunan; Xu, Xiulai
2015-01-01T23:59:59.000Z
We study the coupling between photonic molecules and waveguides in photonic crystal slab structures using finite-difference time-domain method and coupled mode theory. In a photonic molecule with two cavities, the coupling of cavity modes results in two super-modes with symmetric and anti-symmetric field distributions. When two super-modes are excited simultaneously, the energy of electric field oscillates between the two cavities. To excite and probe the energy oscillation, we integrate photonic molecule with two photonic crystal waveguides. In coupled structure, we find that the quality factors of two super-modes might be different because of different field distributions of super-modes. After optimizing the radii of air holes between two cavities of photonic molecule, nearly equal quality factors of two super-modes are achieved, and coupling strengths between the waveguide modes and two super-modes are almost the same. In this case, complete energy oscillations between two cavities can be obtained with a p...
Nonlinear Circuit Analysis An Introduction 1. Why nonlinear circuits?
Hart, Gus
Nonlinear Circuit Analysis An Introduction 1. Why nonlinear circuits? Electrical devices: the oscillator. 2. What is a nonlinear circuit? It is easy to understand the difference between a linear and a nonlinear circuit by looking at the difference between a linear and a nonlinear equation: y x ˇ 2 (1) y
Stationary nonlinear Airy beams
Lotti, A. [Dipartimento di Fisica e Matematica, Universita del'Insubria, Via Valleggio 11, I-22100 Como (Italy); Centre de Physique Theorique, CNRS, Ecole Polytechnique, F-91128 Palaiseau (France); Faccio, D. [Dipartimento di Fisica e Matematica, Universita del'Insubria, Via Valleggio 11, I-22100 Como (Italy); School of Engineering and Physical Sciences, SUPA, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Couairon, A. [Centre de Physique Theorique, CNRS, Ecole Polytechnique, F-91128 Palaiseau (France); Papazoglou, D. G. [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology, Hellas (FORTH), P.O. Box 1527, GR-71110 Heraklion (Greece); Materials Science and Technology Department, University of Crete, GR-71003 Heraklion (Greece); Panagiotopoulos, P.; Tzortzakis, S. [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology, Hellas (FORTH), P.O. Box 1527, GR-71110 Heraklion (Greece); Abdollahpour, D. [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology, Hellas (FORTH), P.O. Box 1527, GR-71110 Heraklion (Greece); Physics Department, University of Crete, GR-71003 Heraklion (Greece)
2011-08-15T23:59:59.000Z
We demonstrate the existence of an additional class of stationary accelerating Airy wave forms that exist in the presence of third-order (Kerr) nonlinearity and nonlinear losses. Numerical simulations and experiments, in agreement with the analytical model, highlight how these stationary solutions sustain the nonlinear evolution of Airy beams. The generic nature of the Airy solution allows extension of these results to other settings, and a variety of applications are suggested.
NONLINEAR OPTICS AT INTERFACES
Chen, Chenson K.
2010-01-01T23:59:59.000Z
Surface Plasmons at a Metal-Dielectric Interface . . . .Plasmons at Metal-Dielectric Interfaces . . . . A. GeneralNONLINEAR OPTICS AT INTERFACES Chenson K. Chen (Ph.D.
World Views From fragmentation
.......................................................11 2. The Seven Components of a World View...................................................... 20 3. The Unity of the Seven Sub........................................... 25 5. The Purpose of the group `Worldviews
Al-Naffouri, Tareq Y.
The Optimum Error Nonlinearity in LMS Adaptation with an Independent and Identically Distributed, CA 94305 Dhahran 31261 USA Saudi Arabia Abstract The class of LMS algorithms employing a gen- eral view of error nonlinearities in LMS adaptation. In particular, it subsumes two recently developed
Hollow waveguides for gas sensing and near-IR applications David J. Haan and James A. Harrington
limited flexibility, so polycarbonate substrate waveguides offer an advantage over silica guides remains straight, and then the guide can be coiled at a later time. A typical polycarbonate waveguide can be coiled to a 4 cm diameter. The behavior of polycarbonate waveguides at longer wavelengths has been
12 optical waveguide filters based on multimode interference for 1.3-and 1.55-m
the theory of large single-mode rib waveguides, the width of the rib waveguide and its height and etched carrying different information and can be used to increase the channel infor- mation capacity of optical, the device structure and the principle of operation are de- scribed. Second, the single-mode rib waveguide
Polymer-based thermo-optic waveguide beam deflector with novel dual folded-thin-strip heating
Chen, Ray
Polymer-based thermo-optic waveguide beam deflector with novel dual folded-thin-strip heating 78758 E-mail: raychen@uts.cc.utexas.edu Abstract. A new design scheme for a polymeric waveguide thermo; integrated optics; optical switches; optical waveguides; polymers; thermo-optic effects. Paper 020173
Weeks, Eric R.
NEWS & VIEWS Glass dynamics Diverging views on glass transition Gregory B. mc.mckenna@ttu.edu T he glass transition is one of the most intriguing phenomena in the world of soft condensed matter. Despite decades of study, many aspects of the behaviour of glass-forming liquids remain elusive
Variable nonlinear resistances
Howard, James Edgar
1955-01-01T23:59:59.000Z
VARIETAL". NONLINEAR RESIS'IANCES A Thes1s JA'. 4ES EDGAR HOWARD as to style and content by Head Department January 1955 LIBRARY A 4 IS COLLEGE PF TEXAS VARIABLE NONLINEAR RESISTANCES A Thesis By JAMES EDGAR HOWARD Submitted...
Generalized transverse Bragg waveguides D. B. Burckel* and S. R. J. Brueck
New Mexico, University of
.4480) Optical amplifiers References and links 1. P. Yeh and A. Yariv, "Bragg Reflection Waveguides," Opt. Commun. 19, 427-430 (1976). 2. A. Y. Cho. A. Yariv and P. Yeh, "Observation of confined propagation in Bragg). 6. A. Yariv, "Coupled-wave formalism for optical waveguiding by transverse Bragg reflection," Opt
Hollow-waveguide delivery systems for high-power, industrial CO2 lasers
to ensure that none of the laser power is focused onto the wall of the waveguide, as immediateHollow-waveguide delivery systems for high-power, industrial CO2 lasers Ricky K. Nubling and James to deliver CO2 laser power for industrial laser applications. The transmission, bending loss, and output
Conditions for designing single-mode air-core waveguides in three-dimensional photonic crystals
Fan, Shanhui
Conditions for designing single-mode air-core waveguides in three-dimensional photonic crystals that allows the design of single-mode air-core waveguides in three-dimensional photonic crystals the regions of maximal electric-field intensity, and placing the air defects to enclose these regions
Bounds for the Distance Dependence of Correlation Functions of Entangled Photons in Waveguides
Andrei Khrennikov; Borje Nilsson; Sven Nordebo; Igor Volovich
2011-05-30T23:59:59.000Z
The distance dependence of the probability of observing two photons in a waveguide is investigated. The Glauber correlation functions of the entangled photons in waveguides are considered and the spatial and temporal dependence of the correlation functions is evaluated. We derive upper bounds to the distance dependence of the probability of observing two photons. These inequalities should be possible to observe in experiments.
New Mexico, University of
optical fiber taper waveguides Kartik Srinivasan,1, * Andreas Stintz,2 Sanjay Krishna,2 and Oskar Painter1 November 2005 Optical fiber taper waveguides are used to improve the efficiency of room temperature. As a near-field collection optic, the fiber taper improves the collection efficiency from microdisk lasers
Polymer Waveguides and Thermo-Optic Switches for an Optical True Time Delay Phased Array Antenna
Chen, Ray
Polymer Waveguides and Thermo-Optic Switches for an Optical True Time Delay Phased Array Antenna device size. 2x2 thermo-optic TIR switches were fabricated with insertion losses of 2.8 dB. A 4-bit TTD loss of 23.88 dB. Keywords: Optical Waveguide, Phased Array Antenna, Thermo-Optic Switch, Polymer
Chen, Ray
High-performance polyimide waveguide array with micro mirror coupler for guided-wave optoelectronicTexas at Austin, Austin, TX 78758 ABSTRACT We report the formation of high-performance polyimide waveguide array. We employed the Si CMOS process compatible polyimide as the fabrication material, which is relatively
Quasi-transverse electromagnetic modes supported by a graphene parallel-plate waveguide
Hanson, George
in a hexagonal structure. Intrinsic graphene is a zero bandgap semiconductor that is very promising for emergingQuasi-transverse electromagnetic modes supported by a graphene parallel- plate waveguide George W October 2008 A model is developed for a parallel-plate waveguide formed by graphene. The graphene
Graded-index Polymer Multimode Waveguides for 100 Gb/s Board-level Data Transmission
Chen, Jian; Bamiedakis, Nikos; Vasil'ev, Peter; Edwards, Tom J.; Brown, Christian T. A.; Penty, Richard V.; White, Ian H.
2015-01-01T23:59:59.000Z
m Long Multimode Polymer Spiral Waveguide for Board-Level Optical Interconnects,” J. Lightwave Technol., Vol. 33, no.4, pp. 1-7 (2015). [7] B.W. Swatowski et al., “Graded index silicone waveguides for high performance computing,” in Proc. IEEE...
Zero-mode clad waveguides for performing spectroscopy with confined effective observation volumes
Levene, Michael J.; Korlach, Jonas; Turner, Stephen W.; Craighead, Harold G.; Webb, Watt W.
2005-07-12T23:59:59.000Z
The present invention is directed to a method and an apparatus for analysis of an analyte. The method involves providing a zero-mode waveguide which includes a cladding surrounding a core where the cladding is configured to preclude propagation of electromagnetic energy of a frequency less than a cutoff frequency longitudinally through the core of the zero-mode waveguide. The analyte is positioned in the core of the zero-mode waveguide and is then subjected, in the core of the zero-mode waveguide, to activating electromagnetic radiation of a frequency less than the cut-off frequency under conditions effective to permit analysis of the analyte in an effective observation volume which is more compact than if the analysis were carried out in the absence of the zero-mode waveguide.
Fabrication and characterization of submicron polymer waveguides by micro-transfer molding
Wu, Te-Wei
2009-12-15T23:59:59.000Z
Various methods exist for fabrication of micron and submicron sized waveguide structures. However, most of them include expensive and time consuming semiconductor fabrication techniques. An economical method for fabricating waveguide structures is introduced and demonstrated in this thesis. This method is established based on previously well-developed photonic crystal fabrication method called two-polymer microtransfer molding. The waveguide in this work functions by a coupler structure that diffracts the incident light into submicron polymer rods. The light is then guided through the rods. Characterization is done by collecting the light that has been guided through the waveguide and exits the end of these submicron polymer bars. The coupling and waveguiding capabilities are demonstrated using two light sources, a laser and white light.
Siwak, N. P. [Department of Electrical and Computer Engineering, Institute for Systems Research, University of Maryland, College Park, Maryland 20742 (United States); Laboratory for the Physical Sciences, 8050 Greenmead Drive, College Park, Maryland 20740 (United States); Fan, X. Z.; Ghodssi, R. [Department of Electrical and Computer Engineering, Institute for Systems Research, University of Maryland, College Park, Maryland 20742 (United States); Kanakaraju, S.; Richardson, C. J. K. [Laboratory for the Physical Sciences, 8050 Greenmead Drive, College Park, Maryland 20740 (United States)
2014-10-06T23:59:59.000Z
An integrated photodiode displacement readout scheme for a microelectromechanical cantilever waveguide resonator sensing platform is presented. III-V semiconductors are used to enable the monolithic integration of passive waveguides with active optical components. This work builds upon previously demonstrated results by measuring the displacement of cantilever waveguide resonators with on-chip waveguide PIN photodiodes. The on-chip integration of the readout provides an additional 70% improvement in mass sensitivity compared to off-chip photodetector designs due to measurement stability and minimized coupling loss. In addition to increased measurement stability, reduced packaging complexity is achieved due to the simplicity of the readout design. We have fabricated cantilever waveguides with integrated photodetectors and experimentally characterized these cantilever sensors with monolithically integrated PIN photodiodes.
Graphene Based Waveguide Polarizers: In-Depth Physical Analysis and Relevant Parameters
de Oliveira, Rafael E P
2015-01-01T23:59:59.000Z
Optical polarizing devices exploiting graphene embedded in waveguides have been demonstrated in the literature recently and both the TE- and TM-pass behaviors were reported. The determination of the passing polarization is usually attributed to graphene's Fermi level (and, therefore, doping level), with, however, no direct confirmation of this assumption provided. Here we show, through numerical simulation, that rather than graphene's Fermi level, the passing polarization is determined by waveguide parameters, such as the superstrate refractive index and the waveguide's height. The results provide a consistent explanation for experimental results reported in the literature. In addition, we show that with an accurate graphene modeling, a waveguide cannot be switched between TE pass and TM pass via Fermi level tuning. Therefore, the usually overlooked contribution of the waveguide design is shown to be essential for the development of optimized TE- or TM-pass polarizers, which we show to be due to the control i...
Optimization Online - Nonlinear Optimization Submissions - 2014
Nonlinear Optimization Submissions - 2014. January 2014. Constrained Nonlinear Optimization New active set identification for general constrained ...
Waveguide, Photodetector, and Imaging Applications of Microspherical Photonics
Allen, Kenneth W
2015-01-01T23:59:59.000Z
Dielectric microspheres with diameters on the order of several wavelengths of light have attracted increasing attention from the photonics community due to their ability to produce extraordinarily tightly focused beams termed photonic nanojets, to be used as microlenses for achieving optical super-resolution or to develop sensors based on whispering-gallery mode resonances. In this dissertation, we study the optical properties of more complicated structures formed by multiple spheres which can be assembled as linear chains, clusters or arrays, integrated with waveguides or embedded inside other materials to achieve new optical properties or device functionalities.
Microsphere-chain waveguides: Focusing and transport properties
Allen, Kenneth W., E-mail: kallen62@uncc.edu; Astratov, Vasily N., E-mail: astratov@uncc.edu [Department of Physics and Optical Science, Center for Optoelectronics and Optical Communications, University of North Carolina at Charlotte, Charlotte, North Carolina 28223-0001 (United States); Air Force Research Laboratory, Sensors Directorate, Wright Patterson AFB, Ohio 45433 (United States); Darafsheh, Arash; Abolmaali, Farzaneh [Department of Physics and Optical Science, Center for Optoelectronics and Optical Communications, University of North Carolina at Charlotte, Charlotte, North Carolina 28223-0001 (United States); Mojaverian, Neda; Limberopoulos, Nicholaos I. [Air Force Research Laboratory, Sensors Directorate, Wright Patterson AFB, Ohio 45433 (United States); Lupu, Anatole [Institut d'Electronique Fondamentale, UMR 8622 CNRS, Universite Paris-Sud XI, 91405 Orsay (France)
2014-07-14T23:59:59.000Z
It is shown that the focusing properties of polystyrene microsphere-chain waveguides (MCWs) formed by sufficiently large spheres (D???20?, where D is the sphere diameter and ? is the wavelength of light) scale with the sphere diameter as predicted by geometrical optics. However, this scaling behavior does not hold for mesoscale MCWs with D???10? resulting in a periodical focusing with gradually reducing beam waists and in extremely small propagation losses. The observed effects are related to properties of nanojet-induced and periodically focused modes in such structures. The results can be used for developing focusing microprobes, laser scalpels, and polarization filters.
Mahler, D. Luke
NEWS AND VIEWS PERSPECTIVE Niche diversification follows key innovation in Antarctic fish radiation Oxford Street, Cambridge MA 02138, USA Antarctic notothenioid fishes provide a fascinating evolu- tionary diversification has occurred repeatedly and in parallel. Keywords: community ecology, fish, macroevolution, phylo
Forward viewing OCT endomicroscopy
Liang, Kaicheng
2014-01-01T23:59:59.000Z
A forward viewing fiber optic-based imaging probe device was designed and constructed for use with ultrahigh speed optical coherence tomography in the human gastrointestinal tract. The light source was a MEMS-VCSEL at 1300 ...
Barran, Brian Arthur
2006-08-16T23:59:59.000Z
This thesis presents a method for simulating fluids on a view dependent grid structure to exploit level-of-detail with distance to the viewer. Current computer graphics techniques, such as the Stable Fluid and Particle Level Set methods...
Laser illumination of multiple capillaries that form a waveguide
Dhadwal, H.S.; Quesada, M.A.; Studier, F.W.
1998-08-04T23:59:59.000Z
A system and method are disclosed for efficient laser illumination of the interiors of multiple capillaries simultaneously, and collection of light emitted from them. Capillaries in a parallel array can form an optical waveguide wherein refraction at the cylindrical surfaces confines side-on illuminating light to the core of each successive capillary in the array. Methods are provided for determining conditions where capillaries will form a waveguide and for assessing and minimizing losses due to reflection. Light can be delivered to the arrayed capillaries through an integrated fiber optic transmitter or through a pair of such transmitters aligned coaxially at opposite sides of the array. Light emitted from materials within the capillaries can be carried to a detection system through optical fibers, each of which collects light from a single capillary, with little cross talk between the capillaries. The collection ends of the optical fibers can be in a parallel array with the same spacing as the capillary array, so that the collection fibers can all be aligned to the capillaries simultaneously. Applicability includes improving the efficiency of many analytical methods that use capillaries, including particularly high-throughput DNA sequencing and diagnostic methods based on capillary electrophoresis. 35 figs.
Slow wave structures using twisted waveguides for charged particle applications
Kang, Yoon W.; Fathy, Aly E.; Wilson, Joshua L.
2012-12-11T23:59:59.000Z
A rapidly twisted electromagnetic accelerating structure includes a waveguide body having a central axis, one or more helical channels defined by the body and disposed around a substantially linear central axial channel, with central portions of the helical channels merging with the linear central axial channel. The structure propagates electromagnetic waves in the helical channels which support particle beam acceleration in the central axial channel at a phase velocity equal to or slower than the speed of light in free space. Since there is no variation in the shape of the transversal cross-section along the axis of the structure, inexpensive mechanical fabrication processes can be used to form the structure, such as extrusion, casting or injection molding. Also, because the field and frequency of the resonant mode depend on the whole structure rather than on dimensional tolerances of individual cells, no tuning of individual cells is needed. Accordingly, the overall operating frequency may be varied with a tuning/phase shifting device located outside the resonant waveguide structure.
Lyapunov functions nonlinear spaces
Hafstein, Sigurđur Freyr
Lyapunov functions on nonlinear spaces R. Sepulchre -- University of Liege, Belgium Reykjavik - July 2013 Constructing Lyapunov functions: a personal journey · Lyap functions in linear spaces (1994: homogeneous spaces with flat, positive, and negative curvature) Lyapunov functions in linear spaces 3
Separable nonlinear programming
Bunton, Wiley Ray
1963-01-01T23:59:59.000Z
. . . An Example . . Development of the Simplex Algorithm Definition of Nonlinear Programming . Survey of Nonlinear Methods. . . . . . II. MILLER'S METHOD 10 The Algorithm. An Example . . Termination and Optimality. . . . . . . . . . . Modeling Devices... oils. In order to maximize daily profits. how much of each motor fuel should be made and how should the raw stocks be blended? Let: motor fuel A = premium gasoline motor fuel 8 = regular gasoline and let subscripts p and r refer to premium...
Integration of a terahertz quantum cascade laser with a hollow waveguide
Wanke, Michael C. (Albuquerque, NM); Nordquist, Christopher D. (Albuquerque, NM)
2012-07-03T23:59:59.000Z
The present invention is directed to the integration of a quantum cascade laser with a hollow waveguide on a chip to improve both the beam pattern and manufacturability. By coupling the QCL output into a single-mode rectangular waveguide the radiation mode structure can be known and the propagation, manipulation, and broadcast of the QCL radiation can then be entirely controlled by well-established rectangular waveguide techniques. By controlling the impedance of the interface, enhanced functions, such as creating amplifiers, efficient coupling to external cavities, and increasing power output from metal-metal THz QCLs, are also enabled.
Optical ridge waveguides in AlGaAs and LiNbO3
Terry, Roger Mark
1993-01-01T23:59:59.000Z
the properties of ridge waveguides in AlGaAs, and also to develop and characterize low loss optical waveguides in LiNbOs that combine ridge geometry with the photoelastic efFect. A model that predicts strain contours and related ref'ractive index distribution... waveguides is important. This would establish profiles of the index distribution and guided modal fields, and permit adjustments of ridge height and film thickness for obtaining maximum coupling efilciencies. A computer model using the relaxation method...
One-dimensional electromagnetic band gap structures formed by discharge plasmas in a waveguide
Arkhipenko, V. I.; Simonchik, L. V., E-mail: l.simonchik@dragon.bas-net.by; Usachonak, M. S. [B.I. Stepanov Institute of Physics of the NAS of Belarus, Ave. Nezavisimostsi 68, 220072 Minsk (Belarus); Callegari, Th.; Sokoloff, J. [Université de Toulouse, UPS, INPT, LAPLACE, Laboratoire Plasma et Conversion d'Energie, 118 route de Narbonne, F-31062 Toulouse cedex 9 (France)
2014-09-28T23:59:59.000Z
We demonstrate the ability to develop one-dimensional electromagnetic band gap structure in X-band waveguide solely by using the positive columns of glow discharges in neon at the middle pressure. Plasma inhomogeneities are distributed uniformly along a typical X-band waveguide with cross section of 23×10 mm˛. It is shown that electron densities larger than 10ą? cm ?ł are needed in order to create an effective one-dimensional electromagnetic band gap structure. Some applications for using the one-dimensional electromagnetic band gap structure in waveguide as a control of microwave (broadband filter and device for variation of pulse duration) are demonstrated.
Sung, Won Ju
2013-12-10T23:59:59.000Z
polarization converters with a phase shifter centered between them and all integrated on a single optical channel waveguide was used. The polarization converters provided a means to control the polarization, and the phase shifter offered a tool to maintain...
Luminescence dynamics and waveguide applications of europium doped gallium nitride powder
Lipson, Michal
Luminescence dynamics and waveguide applications of europium doped gallium nitride powder Carl B, bismuth shot, and europium ingot in an ammonia ambient to initially obtain chunks of the desired material
Tunable Substrate Integrated Waveguide Filters Implemented with PIN Diodes and RF MEMS Switches
Armendariz, Marcelino
2012-02-14T23:59:59.000Z
This thesis presents the first fully tunable substrate integrated waveguide (SIW) filter implemented with PIN diodes and RF MEMS switches. The methodology for tuning SIW filters is explained in detail and is used to create three separate designs...
Lee, Sunwoong
2006-01-01T23:59:59.000Z
Methods are developed for passive source localization and environmental parameter estimation in seismo-acoustic waveguides by exploiting the dispersive behavior of guided wave propagation. The methods developed are applied ...
Silver/polystyrene-coated hollow glass waveguides for the transmission of terahertz radiation
earlier work in- volved the deposition of Ag or Cu coatings inside polycarbonate tubing to form THz-coated hol- low polycarbonate waveguide. To reduce the loss, it is necessary to deposit a dielectric coating
Si?-implanted Si-wire waveguide photodetectors for the mid...
Office of Scientific and Technical Information (OSTI)
provided as a public service. Visit OSTI to utilize additional information resources in energy science and technology. CMOS-compatible Si-implanted Si-waveguide p-i-n...
Vertical coupling of laser glass microspheres to buried silicon nitride ellipses and waveguides
Navarro-Urrios, Daniel; Capuj, Nestor E; Berencen, Yonder; Garrido, Blas; Tredicucci, Alessandro
2015-01-01T23:59:59.000Z
We demonstrate the integration of Nd3+ doped Barium-Titanium-Silicate microsphere lasers with a Silicon Nitride photonic platform. Devices with two different geometrical configurations for extracting the laser light to buried waveguides have been fabricated and characterized. The first configuration relies on a standard coupling scheme, where the microspheres are placed over strip waveguides. The second is based on a buried elliptical geometry whose working principle is that of an elliptical mirror. In the latter case, the input of a strip waveguide is placed on one focus of the ellipse, while a lasing microsphere is placed on top of the other focus. The fabricated elliptical geometry (ellipticity=0.9) presents a light collecting capacity that is 50% greater than that of the standard waveguide coupling configuration and could be further improved by increasing the ellipticity. Moreover, since the dimensions of the spheres are much smaller than those of the ellipses, surface planarization is not required. On th...
Waveguiding at the Edge of a Three-Dimensional Photonic Crystal
Joannopoulos, John D.
We find that electromagnetic waves can be guided at the edge of a three-dimensional photonic crystal in air. When the waveguide is defined by the intersection of two surface planes, the edge modes are associated with the ...
Simple route to ridge optical waveguide fabricated via controlled evaporative self-assembly
Lin, Zhiqun
on stripe patterns formed by CESA. The optical mode of the resulting waveguides was confirmed by exposing cylindrical lens was situated on a lower stationary flat substrate with a drop of PMMAtoluene solution loaded
Optical loss reduction in HIC chalcogenide glass waveguides via thermal reflow
Hu, Juejun
A rapid thermal reflow technique is applied to high-index-contrast, sub-micron waveguides in As[subscript 2]S[subscript 3] chalcogenide glass to reduce sidewall roughness and associated optical scattering loss. Up to 50% ...
Tunable Substrate Integrated Waveguide Filters Implemented with PIN Diodes and RF MEMS Switches
Armendariz, Marcelino
2012-02-14T23:59:59.000Z
This thesis presents the first fully tunable substrate integrated waveguide (SIW) filter implemented with PIN diodes and RF MEMS switches. The methodology for tuning SIW filters is explained in detail and is used to create three separate designs...
Density modification by two superposing TE{sub 10} modes in a plasma filled rectangular waveguide
Tomar, Sanjay K.; Malik, Hitendra K. [Plasma Waves and Particle Acceleration Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110 016 (India)] [Plasma Waves and Particle Acceleration Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110 016 (India)
2013-07-15T23:59:59.000Z
Microwave and plasma interaction is examined via two fundamental TE{sub 10} modes propagating in a plasma filled rectangular waveguide after superposing at a smaller angle. The propagation of the resultant mode realized from these two modes is governed by a wave equation obtained using the Maxwell's equations. This equation is solved numerically using fourth order Runge-Kutta method for the field amplitude of the microwave in the waveguide considering the waveguide to be made up of a perfect conductor and filled with different types of initial plasma density distributions, viz. homogeneous density, linear density with gradient in the propagation direction, and the density with Gaussian profile along the waveguide width. A phenomenon similar to the duct formation by high power microwaves is found to take place, where the plasma density attains interesting profiles. These profiles can be controlled by the angle of superposition, phase difference between the fields of the two modes, microwave frequency and microwave field amplitude.
Dielectric profile variations in high-index-contrast waveguides, coupled mode theory high dielec- tric contrast profiles standard perturbation formulations fails when applied for the high-index-contrast discontinuous dielectric profiles. Among others, our formulation allows
Theory for optimal design of waveguiding light concentrators in photovoltaic microcell arrays
Rogers, John A.
Theory for optimal design of waveguiding light concentrators in photovoltaic microcell arrays of ultrathin flexible solar photovoltaic silicon microcell arrays can be significantly improved using collectors do not result in their indirect gain degradation compared to flat solar concentrators
Tunable dynamic Fano resonances in coupled-resonant optical waveguide
Longhi, Stefano
2015-01-01T23:59:59.000Z
A route toward lineshape engineering of Fano resonances in photonic structures is theoretically proposed, which uses dynamic modulation of the refractive index of a microcavity. The method is exemplified by considering coupled-resonator optical waveguide systems. An exact Floquet analysis, based on coupled-mode theory, is presented. Two distinct kinds of resonances can be dynamically created, depending on whether the static structure sustains a localized mode or not. In the former case a single Fano resonance arises, which can be tuned in both frequency and line width by varying the refractive index modulation amplitude and frequency. In the latter case two resonances, in the form of narrow asymmetric dips in the transmittance, are found, which can overlap resulting in an electromagnetically-induced transparency effect.
Excitation Theory for Space-Dispersive Active Media Waveguides
Barybin, A A
1999-01-01T23:59:59.000Z
A unified electrodynamic approach to the guided-wave excitation theory is generalized to the waveguiding structures containing a hypothetical space-dispersive medium with drifting charge carriers possessing simultaneously elastic, piezoelectric and magnetic properties. Substantial features of our electrodynamic approach are: (i) the allowance for medium losses and (ii) the separation of potential fields peculiar to the slow quasi-static waves. It is shown that the orthogonal complementary fields appearing inside the external source region are just associated with a contribution of the potential fields inherent in exciting sources. Taking account of medium losses converts the usual orthogonality relation into a novel form called the quasi-orthogonality relation. It is found that the separation of potential fields reveals the fine structure of interaction between the exciting sources and mode eigenfields: in addition to the exciting currents interacting with the curl fields, the exciting charges and the double ...
Application of Plasma Waveguides to High Energy Accelerators
Milchberg, Howard M
2013-03-30T23:59:59.000Z
The eventual success of laser-plasma based acceleration schemes for high-energy particle physics will require the focusing and stable guiding of short intense laser pulses in reproducible plasma channels. For this goal to be realized, many scientific issues need to be addressed. These issues include an understanding of the basic physics of, and an exploration of various schemes for, plasma channel formation. In addition, the coupling of intense laser pulses to these channels and the stable propagation of pulses in the channels require study. Finally, new theoretical and computational tools need to be developed to aid in the design and analysis of experiments and future accelerators. Here we propose a 3-year renewal of our combined theoretical and experimental program on the applications of plasma waveguides to high-energy accelerators. During the past grant period we have made a number of significant advances in the science of laser-plasma based acceleration. We pioneered the development of clustered gases as a new highly efficient medium for plasma channel formation. Our contributions here include theoretical and experimental studies of the physics of cluster ionization, heating, explosion, and channel formation. We have demonstrated for the first time the generation of and guiding in a corrugated plasma waveguide. The fine structure demonstrated in these guides is only possible with cluster jet heating by lasers. The corrugated guide is a slow wave structure operable at arbitrarily high laser intensities, allowing direct laser acceleration, a process we have explored in detail with simulations. The development of these guides opens the possibility of direct laser acceleration, a true miniature analogue of the SLAC RF-based accelerator. Our theoretical studies during this period have also contributed to the further development of the simulation codes, Wake and QuickPIC, which can be used for both laser driven and beam driven plasma based acceleration schemes. We will continue our development of advanced simulation tools by modifying the QuickPIC algorithm to allow for the simulation of plasma particle pick-up by the wake fields. We have also performed extensive simulations of plasma slow wave structures for efficient THz generation by guided laser beams or accelerated electron beams. We will pursue experimental studies of direct laser acceleration, and THz generation by two methods, ponderomotive-induced THz polarization, and THz radiation by laser accelerated electron beams. We also plan to study both conventional and corrugated plasma channels using our new 30 TW in our new lab facilities. We will investigate production of very long hydrogen plasma waveguides (5 cm). We will study guiding at increasing power levels through the onset of laser-induced cavitation (bubble regime) to assess the role played by the preformed channel. Experiments in direct acceleration will be performed, using laser plasma wakefields as the electron injector. Finally, we will use 2-colour ionization of gases as a high frequency THz source (<60 THz) in order for femtosecond measurements of low plasma densities in waveguides and beams.
Yang, Junfeng
-neutral Torus 2 Climate Change 4 Combustion and Catalysis Laboratory #12;4 5 1Engineering Revolution 5 #12;6 7Columbia Engineering Plus #12;1 1 2 3 4 5 6 Aerial view of Columbia campus with Columbia Engineering-a liated buildings highlighted in blue Columbia Engineering Plus Engineering Revolution 4
Lu, Jen-Tang; Fleischer, Jason W
2015-01-01T23:59:59.000Z
Nonlinear imaging systems can surpass the limits of linear optics, but to date they have all relied on physical media (e.g. crystals) to work. These materials are all constrained by their physical properties, such as frequency selectivity, environmental sensitivity, time behavior, and fixed nonlinear response. Here, we show that electro-optic spatial light modulators (SLMs) can take the place of traditional nonlinear media, provided that there is a feedback between the shape of the object and the pattern on the modulator. This feedback creates a designer illumination that generalizes the field of adaptive optics to include object-dependent patterns. Unlike physical media, the SLM response can provide arbitrary mathematical functions, operate over broad bandwidths at high speeds, and work equally well at high power and single-photon levels. We demonstrate the method experimentally for both coherent and incoherent light.
Mode stabilization mechanism of buried waveguide lasers with lateral diffused junctions
Yu, K.L.; Chen, T.R.; Koren, U.; Lau, K.Y.; Margalit, S.; Yariv, A.
1983-03-01T23:59:59.000Z
The mode stabilization behavior of the buried active waveguide with lateral diffused junction is theoretically investigated. The study shows that for an active waveguide of width around 5 ..mu..m with a lateral diffused junction in the middle, the single fundamental transverse mode is preferred as the injection level is raised. The theoretical results are found to be in good agreement with experimental results observed in the groove transverse junction InGaAsP/InP laser.
Ottinger, Tina Lynette
1997-01-01T23:59:59.000Z
relatively low temperature (300'C) compared to conventional methods (1000 - 1100'C). These are attractive features for reducing scattering effects in optical channel waveguides and allowing the fabrication of low propagation loss waveguides. The tungsten... Titanium Niobate Ba, ?Sr?Ti?Nb, ?O, (BSTN) are of particular interest because of their established technology in providing crystals of excellent optical quality [2]. Table I compares relevant properties of these tungsten-bronze ferroelectrics with Li...
Tunable nonlinear graphene metasurfaces
Smirnova, Daria A; Kivshar, Yuri S; Khanikaev, Alexander B
2015-01-01T23:59:59.000Z
We introduce the concept of nonlinear graphene metasurfaces employing the controllable interaction between a graphene layer and a planar metamaterial. Such hybrid metasurfaces support two types of subradiant resonant modes, asymmetric modes of structured metamaterial elements ("metamolecules") and graphene plasmons exhibiting strong mutual coupling and avoided dispersion crossing. High tunability of graphene plasmons facilitates strong interaction between the subradiant modes, modifying the spectral position and lifetime of the associated Fano resonances. We demonstrate that strong resonant interaction, combined with the subwavelength localization of plasmons, leads to the enhanced nonlinear response and high efficiency of the second-harmonic generation.
Optical pulse dynamics for quantum-dot logic operations in a photonic-crystal waveguide
Ma, Xun; John, Sajeev [Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7 Canada (Canada)
2011-11-15T23:59:59.000Z
We numerically demonstrate all-optical logic operations with quantum dots (QDs) embedded in a bimodal photonic-crystal waveguide using Maxwell-Bloch equations in a slowly varying envelope approximation (SVEA). The two-level QD excitation level is controlled by one or more femtojoule optical driving pulses passing through the waveguide. Specific logic operations depend on the relative pulse strengths and their detunings from an inhomogeneouslly broadened (about 1% for QD transitions centered at 1.5 {mu}m) QD transition. This excitation controlled two-level medium then determines passage of subsequent probe optical pulses. Envelope equations for electromagnetic waves in the linear dispersion and cutoff waveguide modes are derived to simplify solution of the coupled Maxwell-Bloch equations in the waveguide. These determine the quantum mechanical evolution of the QD excitation and its polarization, driven by classical electromagnetic (EM) pulses near a sharp discontinuity in the EM density of states of the bimodal waveguide. Different configurations of the driving pulses lead to distinctive relations between driving pulse strength and probe pulse passage, representing all-optical logic and, or, and not operations. Simulation results demonstrate that such operations can be done on picosecond time scales and within a waveguide length of about 10 {mu}m in a photonic-band-gap (PBG) optical microchip.
Quantum Dynamics of Nonlinear Cavity Systems
Paul D. Nation
2010-09-16T23:59:59.000Z
We investigate the quantum dynamics of three different configurations of nonlinear cavity systems. To begin, we carry out a quantum analysis of a dc superconducting quantum interference device (SQUID) mechanical displacement detector comprised of a SQUID with a mechanically compliant loop segment. The SQUID is approximated by a nonlinear current-dependent inductor, inducing a flux tunable nonlinear Duffing term in the cavity equation of motion. Expressions are derived for the detector signal and noise response where it is found that a soft-spring Duffing self-interaction enables a closer approach to the displacement detection standard quantum limit, as well as cooling closer to the ground state. Next, we make use of a superconducting transmission line formed from an array of dc-SQUIDs for investigating analogue Hawking radiation. Biasing the array with a space-time varying flux modifies the propagation velocity of the transmission line, leading to an effective metric with a horizon. This setup allows for quantum effects such as backreaction and analogue space-time fluctuations on the Hawking process. Finally, we look at a quantum parametric amplifier with dynamical pump mode, viewed as a zero-dimensional model of Hawking radiation from an evaporating black hole. The conditions are derived under which the spectrum of particles generated from vacuum fluctuations deviates from the thermal spectrum predicted for the conventional parametric amplifier. We find that significant deviation occurs once the pump mode (black hole) has released nearly half of its initial energy in the signal (Hawking radiation) and idler (in-falling particle) modes. As a model of black hole dynamics, this finding lends support to the view that late-time Hawking radiation contains information about the quantum state of the black hole and is entangled with the black hole's quantum gravitational degrees of freedom.
Universal nonlinear entanglement witnesses
Kotowski, Marcin; Kotowski, Michal [College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences, Warsaw University, PL-Warszawa (Poland); Center for Theoretical Physics, Polish Academy of Sciences, Aleja Lotnikow 32/44, PL-02-668 Warszawa (Poland); Kus, Marek [Center for Theoretical Physics, Polish Academy of Sciences, Aleja Lotnikow 32/44, PL-02-668 Warszawa (Poland)
2010-06-15T23:59:59.000Z
We give a universal recipe for constructing nonlinear entanglement witnesses able to detect nonclassical correlations in arbitrary systems of distinguishable and/or identical particles for an arbitrary number of constituents. The constructed witnesses are expressed in terms of expectation values of observables. As such, they are, at least in principle, measurable in experiments.
Variable nonlinear resistances
Howard, James Edgar
1955-01-01T23:59:59.000Z
or another. " An 1mportant characterist1c 1n a nonlinear resistor 1s that the res1stor may be varied in linear constant and exponential constant. The resistor must vary exponentially with current I in the following relation- ship R = KI . K is the linea...
Intramolecular and nonlinear dynamics
Davis, M.J. [Argonne National Laboratory, IL (United States)
1993-12-01T23:59:59.000Z
Research in this program focuses on three interconnected areas. The first involves the study of intramolecular dynamics, particularly of highly excited systems. The second area involves the use of nonlinear dynamics as a tool for the study of molecular dynamics and complex kinetics. The third area is the study of the classical/quantum correspondence for highly excited systems, particularly systems exhibiting classical chaos.
Stereoscopic optical viewing system
Tallman, Clifford S. (Walnut Creek, CA)
1987-01-01T23:59:59.000Z
An improved optical system which provides the operator a stereoscopic viewing field and depth of vision, particularly suitable for use in various machines such as electron or laser beam welding and drilling machines. The system features two separate but independently controlled optical viewing assemblies from the eyepiece to a spot directly above the working surface. Each optical assembly comprises a combination of eye pieces, turning prisms, telephoto lenses for providing magnification, achromatic imaging relay lenses and final stage pentagonal turning prisms. Adjustment for variations in distance from the turning prisms to the workpiece, necessitated by varying part sizes and configurations and by the operator's visual accuity, is provided separately for each optical assembly by means of separate manual controls at the operator console or within easy reach of the operator.
Stereoscopic optical viewing system
Tallman, C.S.
1986-05-02T23:59:59.000Z
An improved optical system which provides the operator with a stereoscopic viewing field and depth of vision, particularly suitable for use in various machines such as electron or laser beam welding and drilling machines. The system features two separate but independently controlled optical viewing assemblies from the eyepiece to a spot directly above the working surface. Each optical assembly comprises a combination of eye pieces, turning prisms, telephoto lenses for providing magnification, achromatic imaging relay lenses and final stage pentagonal turning prisms. Adjustment for variations in distance from the turning prisms to the workpiece, necessitated by varying part sizes and configurations and by the operator's visual accuity, is provided separately for each optical assembly by means of separate manual controls at the operator console or within easy reach of the operator.
ARTICLE IN PRESS Nonlinear Analysis ( )
47J25 47J35 Keywords: Nonlinear inequality Dynamical systems method (DSM) Stability a b s t r a c to this inequality is obtained. This inequality is of interest in a study of dynamical systems and nonlinear in a study of the Dynamical Systems Method (DSM) for solving nonlinear equations of the type F(u) = f , where
Optical Theorem in Nonlinear Media
Li, Wei
2015-01-01T23:59:59.000Z
We consider the optical theorem for scattering of electromagnetic waves in nonlinear media. This result is used to obtain the power extinguished from a field by a nonlinear scatterer. The cases of second harmonic generation and the Kerr effect are studied in some detail. Applications to nonlinear apertureless scanning near-field optical microscopy are considered.
Nonlinear chemical dynamics Francesc Sagusa
Epstein, Irving R.
Nonlinear chemical dynamics Francesc Saguésa and Irving R. Epsteinb a Departament de Química Física March 2003 The interdisciplinary field of nonlinear chemical dynamics has grown significantly in breadth an overview of some of the key results of nonlinear chemical dynamics, with emphasis on those areas most
Nonlinear regression Gordon K. Smyth
Smyth, Gordon K.
Nonlinear regression Gordon K. Smyth Volume 3, pp 14051411 in Encyclopedia of Environmetrics (ISBN, 2002 #12;Nonlinear regression The basic idea of nonlinear regression is the same as that of linear regression, namely to relate a response Y to a vector of predictor variables x D x1, . . . , xk T (see Linear
Jan Kyziol; Andrzej Okninski
2012-11-02T23:59:59.000Z
We study dynamics of two coupled periodically driven oscillators. The internal motion is separated off exactly to yield a nonlinear fourth-order equation describing inner dynamics. Periodic steady-state solutions of the fourth-order equation are determined within the Krylov-Bogoliubov-Mitropolsky approach - we compute the amplitude profiles, which from mathematical point of view are algebraic curves. In the present paper we investigate metamorphoses of amplitude profiles induced by changes of control parameters near singular points of these curves. It follows that dynamics changes qualitatively in the neighbourhood of a singular point.
Mining Views: Database Views for Data Mining Hendrik Blockeel #1
Antwerpen, Universiteit
Mining Views: Database Views for Data Mining Hendrik Blockeel #1 , Toon Calders 2 , Elisa Fromont adriana.prado}@ua.ac.be Abstract-- We present a system towards the integration of data mining mining views. We show that several types of patterns and models over the data, such as itemsets
Mining Views: Database Views for Data Mining Hendrik Blockeel1
Antwerpen, Universiteit
Mining Views: Database Views for Data Mining Hendrik Blockeel1 , Toon Calders2 , Elisa Fromont1 model towards the inte- gration of data mining into relational database systems, based on the so called virtual mining views. We show that several types of patterns and models over the data, such as itemsets
Controlling ultrafast currents by the non-linear photogalvanic effect
Wachter, Georg; Lemell, Christoph; Tong, Xiao-Min; Yabana, Kazuhiro; Burgdörfer, Joachim
2015-01-01T23:59:59.000Z
We theoretically investigate the effect of broken inversion symmetry on the generation and control of ultrafast currents in a transparent dielectric (SiO2) by strong femto-second optical laser pulses. Ab-initio simulations based on time-dependent density functional theory predict ultrafast DC currents that can be viewed as a non-linear photogalvanic effect. Most surprisingly, the direction of the current undergoes a sudden reversal above a critical threshold value of laser intensity I_c ~ 3.8*10^13 W/cm2. We trace this switching to the transition from non-linear polarization currents to the tunneling excitation regime. We demonstrate control of the ultrafast currents by the time delay between two laser pulses. We find the ultrafast current control by the non-linear photogalvanic effect to be remarkably robust and insensitive to laser-pulse shape and carrier-envelope phase.
Pinned modes in two-dimensional lossy lattices with local gain and nonlinearity
Ding, Edwin; Chow, K W; Malomed, Boris A
2014-01-01T23:59:59.000Z
We introduce a system with one or two amplified nonlinear sites ("hot spots", HSs) embedded into a two-dimensional linear lossy lattice. The system describes an array of evanescently coupled optical or plasmonic waveguides, with gain applied at selected HS cores. The subject of the analysis is discrete solitons pinned to the HSs. The shape of the localized modes is found in quasi-analytical and numerical forms, using a truncated lattice for the analytical consideration. Stability eigenvalues are computed numerically, and the results are supplemented by direct numerical simulations. In the case of self-focusing nonlinearity, the modes pinned to a single HS are stable or unstable when the nonlinearity includes the cubic loss or gain, respectively. If the nonlinearity is self-defocusing, the unsaturated cubic gain acting at the HS supports stable modes in a small parametric area, while weak cubic loss gives rise to a bistability of the discrete solitons. Symmetric and antisymmetric modes pinned to a symmetric se...
On the Characterization of Classical Dynamical Systems Using Supersymmetric Nonlinear $?$-models
A. J. Niemi; K. Palo
1995-03-13T23:59:59.000Z
We construct a two dimensional nonlinear $\\sigma$-model that describes the Hamiltonian flow in the loop space of a classical dynamical system. This model is obtained by equivariantizing the standard N=1 supersymmetric nonlinear $\\sigma$-model by the Hamiltonian flow. We use localization methods to evaluate the corresponding partition function for a general class of integrable systems, and find relations that can be viewed as generalizations of standard relations in classical Morse theory.
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) |govInstrumentsmfrirtA Journey InsideMicroBooNE LArTPC Sarah Lockwitz, FNAL 2013OctoberTopo II: An EnzymeFeb-15TotalView
Shen, Y.R.; Chen, C.K.; de Castro, A.R.B.
1980-01-01T23:59:59.000Z
Surface electromagnetic waves are waves propagating along the interface of two media. Their existence was predicted by Sommerfield in 1909. In recent years, interesting applications have been found in the study of overlayers and molecular adsorption on surfaces, in probing of phase transitions, and in measurements of refractive indices. In the laboratory, the nonlinear interaction of surface electromagnetic waves were studied. The preliminary results of this recent venture in this area are presented.
Inverse lattice design and its application to bent waveguides
E. Rivera-Mocińos; E. Sadurní
2015-06-12T23:59:59.000Z
This paper is divided in two parts. In the first part, the inverse spectral problem for tight-binding hamiltonians is studied. This problem is shown to have an infinite number of solutions for properly chosen energies. The space of such solutions is characterized by a hypersurface in the space of hopping amplitudes (i.e. couplings), whose dimension is half the number of sites in the array. Low dimensional examples for short chains are carefully studied and a table of exactly solvable inverse problems is provided in terms of Lie algebraic structures. With the aim of providing a method to generate lattice configurations, a set of equations for coupling constants in terms of energies is obtained; this is done by means of a new formula for the calculation of characteristic polynomials. Two examples with randomly generated spectra are studied numerically, leading to peaked distributions of couplings. In the second part of the paper, our results are applied to the design of bent waveguides, reproducing specific spectra below propagation threshold. As a demonstration, the Dirac and the finite oscillator are realized in this way. A few partially isospectral configurations are also presented.
Gravitational quantum states of neutrons in a rough waveguide
A. E. Meyerovich; V. V. Nesvizhevsky
2006-03-22T23:59:59.000Z
A theory of gravitational quantum states of ultracold neutrons in waveguides with absorbing/scattering walls is presented. The theory covers recent experiments in which the ultracold neutrons were beamed between a mirror and a rough scatterer/absorber. The analysis is based on a recently developed theory of quantum transport along random rough walls which is modified in order to include leaky (absorbing) interfaces and, more importantly, the low-amplitude high-aperture roughness. The calculations are focused on a regime when the direct transitions into the continuous spectrum above the absorption threshold dominate the depletion of neutrons from the gravitational states and are more efficient than the processes involving the intermediate states. The theoretical results for the neutron count are sensitive to the correlation radius (lateral size) of surface inhomogeneities and to the ratio of the particle energy to the absorption threshold in a weak roughness limit. The main impediment for observation of the higher gravitational states is the "overhang" of the particle wave functions which can be overcome only by use scatterers with strong roughness. In general, the strong roughness with high amplitude is preferable if one wants just to detect the individual gravitational states, while the strong roughness experiments with small amplitude and high aperture are preferable for the quantitative analysis of the data. We also discuss the ways to further improve the accuracy of calculations and to optimize the experimental regime.
Low loss superconducting titanium nitride coplanar waveguide resonators
Vissers, M. R.; Gao, J.; Wisbey, D. S.; Hite, D. A.; Pappas, D. P. [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); Tsuei, C. C.; Corcoles, A. D.; Steffen, M. [IBM T. J. Watson Research Center, Yorktown Heights, New York 10598 (United States)
2010-12-06T23:59:59.000Z
Thin films of TiN were sputter-deposited onto Si and sapphire wafers with and without SiN buffer layers. The films were fabricated into rf coplanar waveguide resonators, and internal quality factor measurements were taken at millikelvin temperatures in both the many photon and single photon limits, i.e., high and low electric field regimes, respectively. At high field, we found the highest internal quality factors ({approx}10{sup 7}) were measured for TiN with predominantly a (200)-TiN orientation. The (200)-TiN is favored for growth at high temperature on either bare Si or SiN buffer layers. However, growth on bare sapphire or Si(100) at low temperature resulted in primarily a (111)-TiN orientation. Ellipsometry and Auger measurements indicate that the (200)-TiN growth on the bare Si substrates is correlated with the formation of a thin, {approx_equal}2 nm, layer of SiN during the predeposition procedure. On these surfaces we found a significant increase of Q{sub i} for both high and low electric field regimes.
Abdoli-Arani, A.; Jazi, B. [Department of Photonics, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Shokri, B. [Physics Department and Laser-Plasma Research Institute, G. C. Shahid Beheshti University, Tehran (Iran, Islamic Republic of)
2013-02-15T23:59:59.000Z
The dynamics and energy gain of an electron in the field of a transverse magnetic wave propagating inside an elliptical degenerate plasma waveguide is analytically investigated by finding the field components of the TM{sub mr} mode in this waveguide. Besides, by solving the relativistic momentum and energy equations the deflection angle and the acceleration gradient of the electron in the waveguide are obtained. Furthermore, the field components of the hybrid mode and the transferred power in the presence of the magnetic field in this waveguide are found. Also by applying the boundary conditions at the plasma-conductor interface, we calculate the dispersion relation. It is shown that the cutoff frequency of this mode is dependent on the plasma density but independent of the magnetic field. Then, a single-electron model for numerical calculations of the electron deflection angle and acceleration gradient inside the magnetized plasma-filled elliptical waveguide is generally presented to be used as a cascading process for the acceleration purposes.
Protective laser beam viewing device
Neil, George R.; Jordan, Kevin Carl
2012-12-18T23:59:59.000Z
A protective laser beam viewing system or device including a camera selectively sensitive to laser light wavelengths and a viewing screen receiving images from the laser sensitive camera. According to a preferred embodiment of the invention, the camera is worn on the head of the user or incorporated into a goggle-type viewing display so that it is always aimed at the area of viewing interest to the user and the viewing screen is incorporated into a video display worn as goggles over the eyes of the user.
Liu, Ya-Chi
2014-01-14T23:59:59.000Z
0.3 ns, which indicates the proposed structure is very suitable for real applications. Finally, a short partially corrugated tapered waveguide for silicon-based micro-slab waveguide to plasmonic nano-gap waveguide mode conversion at the optical...
Haddadi, Hamed
Novel Fresnel-zoned microstructured fibre for light waveguiding and efficient coupling between SMF, Universit y of Essex Abstract: We describe a low refractive-index contrast (RIC) Fresnel to efficiently couple light between SMF and PhC using a novel Fresnel-zoned (FZ) MSF waveguide lens. Figure 1(a
Plasmon excitation by the Gaussian-like core mode of a photonic crystal waveguide or a fiber
Skorobogatiy, Maksim
Plasmon excitation by the Gaussian-like core mode of a photonic crystal waveguide or a fiber Maksim of a plasmon by the Gaussian-like leaky core mode of a metal covered 1D photonic crystal waveguide or fiber 2006 Optical Society of America OCIS codes: (130.6010) Sensors, (240.6680) Surface plasmons, (230
Low-threshold, mirrorless emission at 981 nm in an Yb,Gd,Lu:KYW inverted rib waveguide laser
Low-threshold, mirrorless emission at 981 nm in an Yb,Gd,Lu:KYW inverted rib waveguide laser Amol for generating short pulses [2]. Liquid phase epitaxy has been used to fabricate planar [3, 4] and channel [5, 6W and a channel waveguide laser with an output power of 11 mW [9]. In this paper we demonstrate mirrorless lasing
Chen, Ray
Polarization-insensitive thermo-optic switch based on multimode polymeric waveguides polarization-insensitive thermo-optic switch based on multimode polymeric waveguides is reported. This device than 20 dB can be achieved with the deviceelectrode interaction length of 30 mm. The thermo
Chen, Ray
waveguide. A parabola-shaped cavity is etched in fluorinated polyimide using oxygen reactive ion etching of the demonstrated device is 2.4 dB or less. Index Terms--Integrated optics, optical waveguides, polyimides, polymers in fluorinated polyimide using oxygen reactive ion etching (RIE). It will become a cornerstone for an integrated
Avrutsky, Ivan
June 15, 1999 / Vol. 24, No. 12 / OPTICS LETTERS 817 Two-dimensional colloidal crystal corrugated colloidal crystals. We report experimental studies of light coupling into and out of the waveguide structure colloidal crystals. Self-assembly of colloid particles occurs on the surface of a planar waveguide
Stimulated Emission from a Single Excited Atom in a Waveguide Eden Rephaeli1,* and Shanhui Fan2,
Fan, Shanhui
Stimulated Emission from a Single Excited Atom in a Waveguide Eden Rephaeli1,* and Shanhui Fan2, 1; published 3 April 2012) We study stimulated emission from an excited two-level atom coupled to a waveguide by the atom, plays a very important role in stimulated emission. Additionally, the temporal duration
Mountain View, California: Fiat Res Publica
Tung, Gregory
1989-01-01T23:59:59.000Z
Mountain View, California: Fiat Res Publica Gregory Tungundifferen tiated. In Mountain View, California (populationtoward San Francisco. Mountain View is avoiding a "just say
Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)
1992-01-01T23:59:59.000Z
A viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching the user's eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage.
Kronberg, J.W.
1992-10-20T23:59:59.000Z
A viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching the user's eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage. 7 figs.
Kiselyov, S.
1993-11-01T23:59:59.000Z
This article reports the observations of correspondents for the Bulletin (two Russian journalists, one based in Moscow, the other in Kiev) who investigated the status of the Soviet Union's Black Sea Fleet and Ukraine's status as a non-nuclear-weapons state. After two years of wrangling and two earlier failed settlements, Russian President Boris Yeltsin met with Ukrainian President Leonid Kravchuk at Massandra in Crimea. On September 3, the leaders announced that Russia would buy out Ukraine's interest in the fleet and lease the port at Sevastopol. The Massandra summit was also supposed to settle Ukraine's status as a non-nuclear-weapons state. Described here are the Kiev-based correspondent's views on the Massandra summit (and its major topics), which was to have been called off by the Russian foreign ministry when Ukrainian Prime Minister Leonid Kuchma resigned.
Kronberg, J.W.
1991-05-08T23:59:59.000Z
This invention consists of a viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching, the user`s eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage.
Metal-ion spin-on glasses: Novel materials for active waveguides
Ashby, C.I.H.; Sullivan, C.T.; Vawter, G.A.; Hohimer, J.P.; Hadley, G.R.; Neal, D.R.
1993-12-31T23:59:59.000Z
Monolithic integration of a rare-earth-ion-based active waveguide on the same wafer as its diode pump laser would permit compact packaging of the technology demonstrated in fiber lasers and amplifiers. This new monolithic technology would offer the potential for developing compact infrared and visible (up-conversion) lasers, amplifiers, and other photonic integrated circuit components. One approach that we are investigating for such monolithic integration uses a high concentration of one or more rare-earth ions incorporated into polysiloxane spin-on glasses that are solvent-cast onto III-V semiconductor wafers. This ``fiber on a chip`` technology substitute a relatively high-ion-concentration, short-length metal-ion spin-on glass (MISOG) waveguide for the low-ion-concentration, long-length fiber. Progress to data on developing MISOG waveguide materials and technology is discussed.
Plasmonic finite-thickness metal-semiconductor-metal waveguide as ultra-compact modulator
Babicheva, Viktoriia E; Lavrinenko, Andrei V
2013-01-01T23:59:59.000Z
We propose a plasmonic modulator with semiconductor gain material for optoelectronic integrated circuits. We analyze properties of a finite-thickness metal-semiconductor-metal (F-MSM) waveguide to be utilized as an ultra-compact and fast plasmonic modulator. The InP-based semiconductor core allows electrical control of signal propagation. By pumping the core we can vary the gain level and thus the transmittance of the whole system. The study of the device was made using both analytical approaches for planar two-dimensional case as well as numerical simulations for finite-width waveguides. We analyze the eigenmodes of the F-MSM waveguide, propagation constant, confinement factor, Purcell factor, absorption coefficient, and extinction ratio of the structure. We show that using thin metal layers instead of thick ones we can obtain higher extinction ratio of the device.
Characterizing the effects of free carriers in fully-etched, dielectric-clad silicon waveguides
Sharma, Rajat; Lin, Hung-Hsi; Vallini, Felipe; Fainman, Yeshaiahu
2015-01-01T23:59:59.000Z
We theoretically characterize the free-carrier plasma dispersion effect in fully-etched silicon waveguides, with various dielectric material claddings, due to fixed and interface charges at the silicon-dielectric interfaces. The values used for these charges are obtained from the measured capacitance-voltage (C-V) characteristics of SiO2, SiNx, and Al2O3 thin films deposited on silicon substrates. The effect of the charges on the properties of silicon waveguides is then calculated using the semiconductor physics tool Silvaco in combination with the finite-difference time-domain (FDTD) method solver Lumerical. Our results show that, in addition to being a critical factor in the analysis of such active devices as capacitively-driven silicon modulators, this effect should also be taken into account when considering the propagation losses of passive silicon waveguides.
Tan, Wee Chong
2012-07-16T23:59:59.000Z
and waveguide dispersion may be present in the system. The average group index of the integrated As2S3 waveguide is 2.36 ? 0.01. iv On-chip optical amplification was achieved through thermal diffusion of erbium into X- cut LiNbO3. The net gain measured... overlap between the pump and the signal. This can be done by doping erbium into As2S3 film using multi-layer magnetron sputtering. The Rutherford backscattering spectroscopy shows that the doping of Er:As2S3 film with 16 layers of erbium is homogeneous...
Real time chemical detection using species selective thin films and waveguide Zeeman interferometry
Grace, K.M.; Shrouf, K. [Los Alamos National Lab., NM (United States); Honkanen, S. [Univ. of Arizona, Tucson, AZ (United States). Optical Sciences Center] [and others
1998-12-01T23:59:59.000Z
The authors present a chemical sensor scheme based on selective sensing surfaces and highly sensitive integrated optical transduction methods. Using self-assembly techniques, species selective thin-films are covalently attached to the surface of Si{sub 3}N{sub 4} channel waveguides to produce robust sensor elements. Exposure to targeted analytes results in the selective absorption of these molecules onto the waveguide surface causing a change in the effective index of the guided modes. These relative changes in effective index between TE and TM modes are precisely measured using Zeeman interferometry. Measurements demonstrate reversible, real time sensing of volatile organic compounds at ppm levels.
Optic for an endoscope/borescope having high resolution and narrow field of view
Stone, Gary F.; Trebes, James E.
2003-10-28T23:59:59.000Z
An optic having optimized high spatial resolution, minimal nonlinear magnification distortion while at the same time having a limited chromatic focal shift or chromatic aberrations. The optic located at the distal end of an endoscopic inspection tool permits a high resolution, narrow field of view image for medical diagnostic applications, compared to conventional optics for endoscopic instruments which provide a wide field of view, low resolution image. The image coverage is over a narrow (<20 degrees) field of view with very low optical distortion (<5% pin cushion or barrel distortion. The optic is also optimized for best color correction as well as to aid medical diagnostics.
Goulielmakis, E.; Max-Planck-Institut fur Quantenoptik
2008-01-01T23:59:59.000Z
g l e - C y c l e Nonlinear Optics E. G o u l i e l m a k iSingle-Cycle Nonlinear Optics E. Goulielmakis *, M.D-85748 Garching. Center for X-Ray Optics, Lawrence Berkeley
The Mathematics of Nonlinear Optics
MĂ©tivier, Guy
The Mathematics of Nonlinear Optics Guy MÂ´etivier March 7, 2009 Contents 1 Introduction 4 2 Examples of equations arising in nonlinear optics 11 3 The framework of hyperbolic systems 18 3.1 Equations Optics 49 5.1 Linear geometric optics . . . . . . . . . . . . . . . . . . . . . . . . . 49 5
Nonlinear friction in quantum mechanics
Roumen Tsekov
2013-03-10T23:59:59.000Z
The effect of nonlinear friction forces in quantum mechanics is studied via dissipative Madelung hydrodynamics. A new thermo-quantum diffusion equation is derived, which is solved for the particular case of quantum Brownian motion with a cubic friction. It is extended also by a chemical reaction term to describe quantum reaction-diffusion systems with nonlinear friction as well.
Non-Hermitian quantum dynamics and entanglement of coupled nonlinear resonators
Evren Karakaya; Ferdi Altintas; Kaan Güven; Özgür E. Müstecapl?o?lu
2015-02-18T23:59:59.000Z
We consider a generalization of recently proposed non-Hermitian model for resonant cavities coupled by a chiral mirror by taking into account number non-conservation and nonlinear interactions. We analyze non-Hermitian quantum dynamics of populations and entanglement of the cavity modes. We find that an interplay of initial coherence and non-Hermitian coupling leads to a counterintuitive population transfer. While an initially coherent cavity mode is depleted, the other empty cavity can be populated more or less than the initially filled one. Moreover, presence of nonlinearity yields population collapse and revival as well as bipartite entanglement of the cavity modes. In addition to coupled cavities, we point out that similar models can be found in $\\mathcal{PT}$ symmetric Bose-Hubbard dimers of Bose-Einstein condensates or in coupled soliton-plasmon waveguides. We specifically illustrate quantum dynamics of populations and entanglement in a heuristic model that we propose for a soliton-plasmon system with soliton amplitude dependent asymmetric interaction. Degree of asymmetry, nonlinearity and coherence are examined to control plasmon excitations and soliton-plasmon entanglement. Relations to $\\mathcal{PT}$ symmetric lasers and Jahn-Teller systems are pointed out.
Sub-wavelength waveguide loaded by a complementary electric metamaterial for vacuum electron devices
Duan, Zhaoyun, E-mail: zhyduan@uestc.edu.cn [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 167 Albany St., Cambridge, Massachusetts 02139 (United States); Institute of High Energy Electronics, School of Physical Electronics, University of Electronic Science and Technology of China, No.4, Section 2, North Jianshe Road, Chengdu 610054 (China); Hummelt, Jason S.; Shapiro, Michael A., E-mail: shapiro@psfc.mit.edu; Temkin, Richard J. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 167 Albany St., Cambridge, Massachusetts 02139 (United States)
2014-10-15T23:59:59.000Z
We report the electromagnetic properties of a waveguide loaded by complementary electric split ring resonators (CeSRRs) and the application of the waveguide in vacuum electronics. The S-parameters of the CeSRRs in free space are calculated using the HFSS code and are used to retrieve the effective permittivity and permeability in an effective medium theory. The dispersion relation of a waveguide loaded with the CeSRRs is calculated by two approaches: by direct calculation with HFSS and by calculation with the effective medium theory; the results are in good agreement. An improved agreement is obtained using a fitting procedure for the permittivity tensor in the effective medium theory. The gain of a backward wave mode of the CeSRR-loaded waveguide interacting with an electron beam is calculated by two methods: by using the HFSS model and traveling wave tube theory; and by using a dispersion relation derived in the effective medium model. Results of the two methods are in very good agreement. The proposed all-metal structure may be useful in miniaturized vacuum electron devices.
Highly dispersive micro-ring resonator based on one dimensional photonic crystal waveguide
Levy, Uriel
one-dimensional systems," IEEE J. Quantum Electron. 39, 364-374 (2003). 11. J. Scheuer and A. Yariv-bandgap microcavities in optical waveguides," Nature 390, 143-145 (1997). 4. A. A. Savchenkov, A. B. Matsko, and L. Muller, A. Wicht, R. H. Rinkleff, and K. Danzmann, "Optical resonator with steep internal dispersion
Slow-light, band-edge waveguides for tunable time delays
delay lines," Phys. Rev. E 68, 066,616 (2003). 5. A. Yariv, Y. Xu, R. K. Lee, and A. Scherer, "Coupled-resonator optical waveguide: a proposal and analysis," Opt. Lett. 24, 711713 (1999). 6. S. Mookherjea and A. Yariv (Academic Press, London, 1998). 3. M. S. Rasras, C. K. Madsen, M. A. Cappuzzo, E. Chen, L. T. Gomez, E. J
Tan, Wee Chong
2012-07-16T23:59:59.000Z
-As2S3 not only produces films that have optical properties closer to their equilibrium state, the as-deposited films also show no signs of photo-decomposed As2O3. The TM propagation loss of the as-deposited As2S3-on-Ti:LiNbO3 waveguide is 0.20 plus...
Bandwidth Studies on Multimode Polymer Waveguides for ? 25 Gb/s Optical Interconnects
Bamiedakis, Nikolaos; Chen, Jian; Penty, Richard V.; White, Ian H.
2014-07-25T23:59:59.000Z
collects the output light and delivers it to the high-speed PD (VIS D30-850M), while a RF amplifier is used to amplify the received electrical signals. Index matching gel is employed at both the waveguide input and output facets to minimise Fresnel...
TESLA-FEL 2003-04 Waveguide Monitors -a New Type of Beam Position
TESLA-FEL 2003-04 Waveguide Monitors - a New Type of Beam Position Monitors for the TTF FEL U. Hahn Laser (FEL) at the TESLA Test Facilty (TTF) requires the electron trajectory to be aligned bench in the laboratory and with beam. TTF FEL measurement results are also presented and possible
Infrared transmissive, hollow plastic waveguides with inner AgAgI coatings
A. Harrington Hollow polycarbonate waveguides with thin-film coatings of AgAgI were fabricated and at the same time maintain good flexibility we have chosen to use polycarbonate tubing with bore sizes ranging from 500 to 2000 m. Polycarbonate tubing is quite flexible in the bore sizes up to 6000 m
Selectively Erbium Doped Titanium Diffused Optical Waveguide Amplifiers in Lithium Niobate
Suh, Jae Woo
2011-02-22T23:59:59.000Z
Selectively erbium (Er) doped titanium (Ti) in-diffused optical waveguide amplifiers on lithium niobate (LiNbO3) substrate have been fabricated and characterized in the wavelength regime around ? = 1.53?m using counter-directional pumping at ?P = 1...
Waveguides in three-dimensional photonic bandgap materials for particle-accelerator on a
Byer, Robert L.
Waveguides in three-dimensional photonic bandgap materials for particle-accelerator on a chip@physics.anu.edu.au Abstract: The quest for less costly and more compact high-energy particle accelerators," in Proceedings of Particle Accelerator Conference 2011, (2011) pp. 277279. 12. M. Deubel, G. von Freymann, M
Surface plasmon modes of finite, planar, metal-insulator-metal plasmonic waveguides
New Mexico, University of
Surface plasmon modes of finite, planar, metal-insulator-metal plasmonic waveguides Jing Chen bound and leaky surface plasmon (SP) modes. The dispersion relations, propagation lengths steering devices. ©2008 Optical Society of America OCIS codes: (240.6680) Surface plasmons; (250
S-Band Waveguide Reconfiguration Options for the LCLS RF Gun and L0 Klystron Feeds
McIntosh, P.
2005-01-28T23:59:59.000Z
This note highlights the possible re-configuration options for the existing WR284 S-band waveguide in the klystron gallery, to enable those existing 5045 klystrons to power the RF Gun and the L0 accelerating structures for LCLS. A reconfiguration decision based on the pros and cons for each option is subsequently identified.
Gain assisted propagation of surface plasmon polaritons on planar metallic waveguides
Fainman, Yeshaiahu
, "Long- wavelength ( 8-11.5 µm) semiconductor lasers with waveguides based on surface plasmons," Opt. Lett. 23, 1366 (1998). 9. E. D. Palik, Handbook of optical constants of solids vol. I (Academic Press, 1985). 10. T. Saitoh and T Mukai, "1.5 µm GaInAsP traveling-wave semiconductor laser amplifier," IEEE J
Semiconductor lasers with broad tunnel-coupled waveguides, emitting at a wavelength of 980 nm
Zvonkov, N B; Ershov, A V; Zvonkov, B N; Maksimov, G A; Uskova, E A [Scientific-Research Physicotechnical Institute at the Nizhnii Novgorod State University, Nizhnii Novgorod (Russian Federation); Akhlestina, S A [Research Insitute of Chemistry, N.I. Lobachevskii Nizhnii Novgorod State University, Nizhnii Novgorod (Russian Federation)
1999-03-31T23:59:59.000Z
InGaP/GaAs/InGaAs semiconductor lasers with broad tunnel-coupled waveguides were developed and investigated experimentally. Output radiation power of 5.2 - 5.8 W was obtained from an emitting region 100 {mu}m wide with a 36{sup 0} divergence of the emitted radiation in a plane perpendicular to the p - n junction. (lasers)
Time-reversal in an ultrasonic waveguide Philippe Roux,a)
Roman, Benoît
Time-reversal in an ultrasonic waveguide Philippe Roux,a) Benoit Roman, and Mathias Fink 3 February 1997 The aim of this letter is to study, by using a time-reversal mirror TRM , ways to the high focusing property obtained with a TRM working in a bounded channel. It will be shown that the time
An integrated thin-film thermo-optic waveguide beam deflector Suning Tang,a)
Chen, Ray
An integrated thin-film thermo-optic waveguide beam deflector Suning Tang,a) Bulang Li, and Xinghua for publication 16 February 2000 We have demonstrated the operation of a thin-film thermo-optical beam deflector-film polymer and silica microprisms as the guiding layer. The beam deflection is achieved through the thermo
Polyimide-waveguide-based thermal optical switch using total-internal-reflection effect
Chen, Ray
Polyimide-waveguide-based thermal optical switch using total-internal-reflection effect Jianyi Yang with an X junction was designed and fabricated by using the thermo-optic effect of polyimide materials and fabricated the TIR TO switch us- ing polyimide materials. The TO effect of polymeric materials is negative, i
ADVANCES IN GEOPHYSICS, VOL. 50, CHAPTER 7 A SCATTERING WAVEGUIDE IN THE
Furumura, Takashi
in the Philippine Sea plate. Seismograms in these high intensity zones show low-frequency ( f in the Philippine Sea plate and in the Pacific plate. A good representation of the behavior of scattering waveguide to the simultaneous subduction of the Pacific plate in northern Japan and the Philippine Sea plate in western Japan
Slab waveguide photobioreactors for microalgae based biofuel production{{ Erica Eunjung Jung,a
Angenent, Lars T.
Slab waveguide photobioreactors for microalgae based biofuel production{{ Erica Eunjung Jung Erickson*a Received 1st May 2012, Accepted 19th June 2012 DOI: 10.1039/c2lc40490g Microalgae than 100% of the existing US cropping area. By contrast, microalgae could meet this demand
Narrow-Line Waveguide Terahertz Time-Domain Spectroscopy of Aspirin and Aspirin Precursors
in a parallel-plate waveguide, where the film is probed by THz radiation. The planar order of the film been some success in the detection and identification of different pharmaceutical molecules,6 primarily in the area of illicit drugs.79 However, the ability to distinguish among these molecules could be greatly
CMOS-compatible Titanium Dioxide Deposition for Athermalization of Silicon Photonic Waveguides
Yoo, S. J. Ben
CMOS-compatible Titanium Dioxide Deposition for Athermalization of Silicon Photonic Waveguides@ucdavis.edu , sbyoo@ucdavis.edu Abstract: We discuss titanium dioxide material development for CMOS compatible fabrication and integration of athermal silicon photonic components. Titanium dioxide overclad ring modulators
Selectively Erbium Doped Titanium Diffused Optical Waveguide Amplifiers in Lithium Niobate
Suh, Jae Woo
2011-02-22T23:59:59.000Z
Selectively erbium (Er) doped titanium (Ti) in-diffused optical waveguide amplifiers on lithium niobate (LiNbO3) substrate have been fabricated and characterized in the wavelength regime around ? = 1.53?m using counter-directional pumping at ?P = 1...
Slab waveguide photobioreactors for microalgae based biofuel production{{ Erica Eunjung Jung,a
Erickson, David
Slab waveguide photobioreactors for microalgae based biofuel production{{ Erica Eunjung Jung are a promising feedstock for sustainable biofuel production. At present, however, there are a number to substantial interest in increasing biofuel production. Biofuels can be produced from a number of different
Confinement of Light in Disordered Photonic Lattices: A New Platform for Waveguidance
Ghosh, Somnath
2015-01-01T23:59:59.000Z
A right amount of disorder in the form of refractive index variation has been introduced to achieve transverse localization of light 1D semi-infinite photonic lattices. Presence of longitudinally-invariant transverse disorder opens-up a new waveguiding mechanism.
Multipacting Simulations of Tuner-adjustable waveguide coupler (TaCo) with CST
Shafqat, Nuaman; Wegner, Rolf
2015-01-01T23:59:59.000Z
Tuner-adjustable waveguide couplers (TaCo) are used to feed microwave power to different RF structures of LINAC4. This paper studies the multipacting phenomenon for TaCo using PIC solver of CST PS. Simulations are performed for complete field sweeps and results are analysed.
Deposition and characterization of metal sulfide dielectric coatings for hollow glass waveguides
HGW at 1.55 µm. ©2003 Optical Society of America OCIS codes: (060.2390) Fiber optics, infrared; (310 by chemical bath deposition for solar energy related applications," Solar Energy Materials and Solar Cells 52 coatings for Ag/dielectric hollow glass waveguides," in Optical Fibers and Sensors for Medical Applications
Analysis of microwave leaky modes propagating through laser plasma filaments column waveguide
Alshershby, Mostafa; Hao Zuoqiang; Lin Jingquan [School of Science, Changchun University of Science and Technology, Changchun 130022 (China)
2012-12-15T23:59:59.000Z
A plasma column waveguide formed by a bundle of closely spaced plasma filaments induced by the propagation of ultrafast laser pulses in air and revived by a longer infrared laser pulse is shown to support microwave radiation. We consider values of both the plasma electron density and microwave frequency for which the refractive index of plasma is lower than the refractive index of air; therefore, a leaky plasma waveguide can be realized in extremely high frequency band. The guiding mechanism does not require high conductance of the plasma and can be easily excited by using commercial femtosecond laser sources. A theoretical study of leaky mode characteristics of isotropic and homogeneous plasma column waveguides is investigated with several values of plasma and waveguide structure parameters. The microwave transmission loss was found to be mainly caused by the microwave leakage through the air-plasma interface and is weakly dependent on the plasma absorption. In spite of losses of microwaves caused by leakage and plasma absorption, it is shown to be much lower than both that accompanying to surface waves attaching to single conducting plasma wire and the free space propagation over distances in the order of the filament length, which opens exciting perspectives for short distance point to point wireless transmission of pulsed-modulated microwaves.
A waveguide model of the return stroke channel with a "metamaterial" corona
Lehtinen, Nikolai G.
) highly conducting thin core channel; (2) "metamaterial" corona, i.e., corona with an effective bulk, 2005], highly conducting thin core surrounded by a perfectly conducting cylindrical shell corona shieldA waveguide model of the return stroke channel with a "metamaterial" corona Nikolai G. Lehtinen1
Test particle simulation of direct laser acceleration in a density-modulated plasma waveguide
Lin, M.-W.; Jovanovic, I. [Department of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
2012-11-15T23:59:59.000Z
Direct laser acceleration (DLA) of electrons by the use of the intense axial electric field of an ultrafast radially polarized laser pulse is a promising technique for future compact accelerators. Density-modulated plasma waveguides can be implemented for guiding the propagation of the laser pulse to extend the acceleration distance and for the quasi-phase-matching between the accelerated electrons and the laser pulse. A test particle model is developed to study the optimal axial density modulation structure of plasma waveguides for laser pulses to efficiently accelerate co-propagating electrons. A simple analytical approach is also presented, which can be used to estimate the energy gain in DLA. The analytical model is validated by the test particle simulation. The effect of injection phase and acceleration of electrons injected at various radial positions are studied. The results indicate that a positively chirped density modulation of the waveguide structure is required to accelerate electron with low initial energies, and can be effectively optimized. A wider tolerance on the injection phase and radial distance from the waveguide axis exists for electrons injected with a higher initial energy.
Asymptotic Solutions of the Leaky Modes and PML Modes in a Pekeris Waveguide
Lu, Ya Yan
in open waveguides. The Perfectly Matched Layer (PML) is a widely used technique for truncating unbounded is highly oscillatory and difficult to evaluate, but it can be re-written as the infinite sum of the leaky is extremely slow corresponding to the existence of spurious reflections from the lower bottom boundary
CEST and MEST: Tools for the Simulation of Radio Frequency Electric Discharges in Waveguides
de Lara, Juan
with the walls. In CR, the discharge occurs at low pressures, with the presence of a gas in the waveguide and is produced by ionization of the gas neutral atoms. For certain pressure ranges, we may find both kind (ripping new electrons from them), or by ionization of the neutral atoms of a gas inside the device. MEST
Paris-Sud XI, Université de
Structure for Low Power and Low Cost Smart Antenna Systems Halim Boutayeb, Paul Watson and Toby Kemp AntennaNew Reconfigurable Power Divider Based on Radial Waveguide and Cylindrical Electromagnetic Band Gap halim.boutayeb@huawei.com Abstract--A new low power and low cost technique is proposed for designing
Sridhar, Srinivas
, and then blow dried with nitrogen. A 150 nm thick titanium mask layer was deposited on the wafers using an e a much higher resistance to optical damage than conventional titanium indiffused LN waveguides, making of this process are as follows: the deposition of titanium and photoresist masks on the LN substrate
Progress in year 2002 1. Propagation of Bose-Einstein condensates in a magnetic waveguide
1 Progress in year 2002 1. Propagation of Bose-Einstein condensates in a magnetic waveguide Progress in the field of atom optics depends on developing improved sources of matter waves and advances source was to make sure that the new cooling cycle did not destroy the condensate held in the reservoir
A Direct Approach to the Electromagnetic Casimir Energy in a Rectangular Waveguide
Madad Ali Valuyan; Reza Moazzemi; Siamak S. Gousheh
2008-06-10T23:59:59.000Z
In this paper we compute the leading order Casimir energy for the electromagnetic field (EM) in an open ended perfectly conducting rectangular waveguide in three spatial dimensions by a direct approach. For this purpose we first obtain the second quantized expression for the EM field with boundary conditions which would be appropriate for a waveguide. We then obtain the Casimir energy by two different procedures. Our main approach does not contain any analytic continuation techniques. The second approach involves the routine zeta function regularization along with some analytic continuation techniques. Our two approaches yield identical results. This energy has been calculated previously for the EM field in a rectangular waveguide using an indirect approach invoking analogies between EM fields and massless scalar fields, and using complicated analytic continuation techniques, and the results are identical to ours. We have also calculated the pressures on different sides and the total Casimir energy per unit length, and plotted these quantities as a function of the cross-sectional dimensions of the waveguide. We also present a physical discussion about the rather peculiar effect of the change in the sign of the pressures as a function of the shape of the cross-sectional area.
Nonlinear arcsin-electrodynamics
S. I. Kruglov
2015-03-21T23:59:59.000Z
A new model of nonlinear electrodynamics with three parameters is suggested and investigated. It is shown that if the external constant magnetic field presents the phenomenon of vacuum birefringence takes place. The indexes of refraction for two polarizations of electromagnetic waves, parallel and perpendicular to the magnetic induction field are calculated. The electric field of a point-like charge is not singular at the origin and the static electric energy is finite. We have calculated the static electric energy of point-like particles for different parameters of the model. The canonical and symmetrical Belinfante energy-momentum tensors and dilatation current are obtained. We demonstrate that the dilatation symmetry and dual symmetry are broken in the model suggested.
Anatoliy K. Prykarpatsky; Nikolai N. Bogolubov; Jolanta Golenia; Ufuk Taneri
2009-02-25T23:59:59.000Z
Introductive backgrounds of a new mathematical physics discipline - Quantum Mathematics - are discussed and analyzed both from historical and analytical points of view. The magic properties of the second quantization method, invented by V. Fock in 1932, are demonstrated, and an impressive application to the nonlinear dynamical systems theory is considered.
The design of a simulated in-line side-coupled 6 MV linear accelerator waveguide
St Aubin, Joel; Steciw, Stephen; Fallone, B. G. [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)
2010-02-15T23:59:59.000Z
Purpose: The design of a 3D in-line side-coupled 6 MV linac waveguide for medical use is given, and the effect of the side-coupling and port irises on the radio frequency (RF), beam dynamics, and dosimetric solutions is examined. This work was motivated by our research on a linac-MR hybrid system, where accurate electron trajectory information for a clinical medical waveguide in the presence of an external magnetic field was needed. Methods: For this work, the design of the linac waveguide was generated using the finite element method. The design outlined here incorporates the necessary geometric changes needed to incorporate a full-end accelerating cavity with a single-coupling iris, a waveguide-cavity coupling port iris that allows power transfer into the waveguide from the magnetron, as well as a method to control the RF field magnitude within the first half accelerating cavity into which the electrons from the gun are injected. Results: With the full waveguide designed to resonate at 2998.5{+-}0.1 MHz, a full 3D RF field solution was obtained. The accuracy of the 3D RF field solution was estimated through a comparison of important linac parameters (Q factor, shunt impedance, transit time factor, and resonant frequency) calculated for one accelerating cavity with the benchmarked program SUPERFISH. It was found that the maximum difference between the 3D solution and SUPERFISH was less than 0.03%. The eigenvalue solver, which determines the resonant frequencies of the 3D side-coupled waveguide simulation, was shown to be highly accurate through a comparison with lumped circuit theory. Two different waveguide geometries were examined, one incorporating a 0.5 mm first side cavity shift and another with a 1.5 mm first side cavity shift. The asymmetrically placed side-coupling irises and the port iris for both models were shown to introduce asymmetries in the RF field large enough to cause a peak shift and skewing (center of gravity minus peak shift) of an initially cylindrically uniform electron beam accelerating within the waveguide. The shifting and skewing of the electron beam were found to be greatest due to the effects of the side-coupling irises on the RF field. A further Monte Carlo study showed that this effect translated into a 1% asymmetry in a 40x40 cm{sup 2} field dose profile. Conclusions: A full 3D design for an in-line side-coupled 6 MV linear accelerator that emulates a common commercial waveguide has been given. The effect of the side coupling on the dose distribution has been shown to create a slight asymmetry, but overall does not affect the clinical applicability of the linac. The 3D in-line side-coupled linac model further provides a tool for the investigation of linac performance within an external magnetic field, which exists in an integrated linac-MR system.
Yang, Peidong; Law, Matt; Sirbuly, Donald J.; Johnson, Justin C.; Saykally, Richard; Fan, Rong; Tao, Andrea
2012-10-02T23:59:59.000Z
Nanoribbons and nanowires having diameters less than the wavelength of light are used in the formation and operation of optical circuits and devices. Such nanostructures function as subwavelength optical waveguides which form a fundamental building block for optical integration. The extraordinary length, flexibility and strength of these structures enable their manipulation on surfaces, including the precise positioning and optical linking of nanoribbon/wire waveguides and other nanoribbon/wire elements to form optical networks and devices. In addition, such structures provide for waveguiding in liquids, enabling them to further be used in other applications such as optical probes and sensors.
Stabilization of three-wave vortex beams in the waveguide
Gammal, Arnaldo
2015-01-01T23:59:59.000Z
We consider two-dimensional (2D) localized vortical modes in the three-wave system with the quadratic ($\\chi ^{(2)}$) nonlinearity, alias nondegenerate second-harmonic-generating system, guided by the isotropic harmonic-oscillator (HO) (alias parabolic) confining potential. In addition to the straightforward realization in optics, the system models mixed atomic-molecular Bose-Einstein condensates (BECs). The main issue is stability of the vortex modes, which is investigated through computation of instability growth rates for eigenmodes of small perturbations, and by means of direct simulations. The threshold of parametric instability for single-color beams, represented solely by the second harmonic (SH) with zero vorticity, is found in an analytical form with the help of the variational approximation (VA). Trapped states with vorticities $\\left( +1,-1,0\\right) $ in the two fundamental-frequency (FF) components and the SH one [the so-called \\textit{hidden-vorticity} (HV) modes] are completely unstable. Also un...
Direct-bandgap electroluminescence from a horizontal Ge p-i-n ridge waveguide on Si(001) substrate
Liu, Zhi; Li, Yaming; He, Chao; Li, Chuanbo; Xue, Chunlai; Zuo, Yuhua; Cheng, Buwen, E-mail: cbw@semi.ac.cn; Wang, Qiming [State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)
2014-05-12T23:59:59.000Z
Horizontal injection Ge p-i-n ridge waveguide light emitting diodes (LEDs) were fabricated on n{sup ?}-Si(001) substrates by ultrahigh vacuum chemical vapor deposition. The direct-bandgap electroluminescence (EL) of Ge waveguide LEDs under a continuous/pulse electrical pump was studied. The heating effect from a continuous electrical pump was found to significantly enhance the emission of devices. The top surface EL intensity of the Ge waveguide LEDs significantly depended on the position. Most direct-bandgap radiative recombination of Ge p-i-n waveguide LEDs occurred near the N{sup +} region of the junction. This interesting phenomenon could be explained by the carrier distribution in the junction and the pseudo-direct bandgap of Ge.
Ignisca, Anamaria
2011-01-01T23:59:59.000Z
In this thesis, we derive full theoretical expressions for the moments of the matched filtered scattered field due to volume inhomogeneities in an ocean waveguide and provide a computationally efficient time harmonic ...
Nonlinear and distributed sensory estimation
Sugathevan, Suranthiran
2005-08-29T23:59:59.000Z
Methods to improve performance of sensors with regard to sensor nonlinearity, sensor noise and sensor bandwidths are investigated and new algorithms are developed. The necessity of the proposed research has evolved from the ever-increasing need...
Reconstruction of nonlinear wave propagation
Fleischer, Jason W; Barsi, Christopher; Wan, Wenjie
2013-04-23T23:59:59.000Z
Disclosed are systems and methods for characterizing a nonlinear propagation environment by numerically propagating a measured output waveform resulting from a known input waveform. The numerical propagation reconstructs the input waveform, and in the process, the nonlinear environment is characterized. In certain embodiments, knowledge of the characterized nonlinear environment facilitates determination of an unknown input based on a measured output. Similarly, knowledge of the characterized nonlinear environment also facilitates formation of a desired output based on a configurable input. In both situations, the input thus characterized and the output thus obtained include features that would normally be lost in linear propagations. Such features can include evanescent waves and peripheral waves, such that an image thus obtained are inherently wide-angle, farfield form of microscopy.
A Regulator's View of Cogeneration
Shanaman, S. M.
1982-01-01T23:59:59.000Z
of the total national electric generation. In view of the energy requirements of Pennsylvania's industry and the impact of increasing energy costs on employment the Commission directed its technical staff to investigate the potential for industrial cogeneration...
A Regulator's View of Cogeneration
Shanaman, S. M.
1982-01-01T23:59:59.000Z
of the total national electric generation. In view of the energy requirements of Pennsylvania's industry and the impact of increasing energy costs on employment the Commission directed its technical staff to investigate the potential for industrial cogeneration...
Dmitriy Palatnik
2005-08-12T23:59:59.000Z
Suggested modification of the Einstein-Maxwell system, such that Maxwell equations become non-gauge and nonlinear. The theory is based on assumption that observable (i.e., felt by particles) metric is $ {\\tilde{g}}_{ab} = g_{ab} - l^2{A}_a{A}_b$, where $g_{ab}$ is metric (found from Einstein equations), $A_a$ is electromagnetic potential, and $l$ is fundamental constant of the theory. Specific model of the mass and charge densities of a fundamental particle is considered. As a result, one obtains solutions corresponding to quantized electrical charge with spectrum $q_{n} = {{2n}\\over3}e$ and $q'_{n} = -{(2n+1)\\over3}e$, where $n = 0, 1, 2, ...$ Theory predicts Coulomb interaction between electrical charges and masses. Namely, if ($m, e$) and ($m',e'$) describe masses and electrical charges of two particles respectively, then energy of interaction (in non-relativistic limit) is $V(r) = [ee' - kmm' - \\sqrt k(em' + e'm)]/r$. It follows, then, that the Earth's mass, $M_E$, contributes negative electrical charge, $Q_E = - \\sqrt k M_E$, which explains why primary cosmic rays consist mainly of positively charged particles. One may attribute the fairweather electric field at the Earth's surface to the charge $Q_E$.
Epstein, Irving R.
FOCUS ISSUE: Nonlinear dynamics related to polymeric systems Overview: Nonlinear dynamics related is another promising practical application of nonlinear chemical dynamics. In this issue we focus on non is known about nonlinear phenom- ena in polymeric systems. One reason for the lack of interest in nonlinear
Foundations of nonlinear gyrokinetic theory
Brizard, A. J.; Hahm, T. S. [Department of Chemistry and Physics, Saint Michael's College, Colchester, Vermont 05439 (United States); Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)
2007-04-15T23:59:59.000Z
Nonlinear gyrokinetic equations play a fundamental role in our understanding of the long-time behavior of strongly magnetized plasmas. The foundations of modern nonlinear gyrokinetic theory are based on three pillars: (i) a gyrokinetic Vlasov equation written in terms of a gyrocenter Hamiltonian with quadratic low-frequency ponderomotivelike terms, (ii) a set of gyrokinetic Maxwell (Poisson-Ampere) equations written in terms of the gyrocenter Vlasov distribution that contain low-frequency polarization (Poisson) and magnetization (Ampere) terms, and (iii) an exact energy conservation law for the gyrokinetic Vlasov-Maxwell equations that includes all the relevant linear and nonlinear coupling terms. The foundations of nonlinear gyrokinetic theory are reviewed with an emphasis on rigorous application of Lagrangian and Hamiltonian Lie-transform perturbation methods in the variational derivation of nonlinear gyrokinetic Vlasov-Maxwell equations. The physical motivations and applications of the nonlinear gyrokinetic equations that describe the turbulent evolution of low-frequency electromagnetic fluctuations in a nonuniform magnetized plasmas with arbitrary magnetic geometry are discussed.
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Calgary, University of
Conversation View Outlook Web App User Guide Email conversations that include multiple replies and sent messages can be viewed simultaneously using Conversation View. In Exchange 2010 Outlook Web App
Anisotropic Ta{sub 2}O{sub 5} waveguide etching using inductively coupled plasma etching
Muttalib, Muhammad Firdaus A., E-mail: mfam1g08@ecs.soton.ac.uk; Chen, Ruiqi Y.; Pearce, Stuart J.; Charlton, Martin D. B. [Nano Research Group, Electronics and Computer Science, Faculty of Physical and Applied Sciences, University of Southampton, Southampton SO17 1BJ (United Kingdom)
2014-07-01T23:59:59.000Z
Smooth and vertical sidewall profiles are required to create low loss rib and ridge waveguides for integrated optical device and solid state laser applications. In this work, inductively coupled plasma (ICP) etching processes are developed to produce high quality low loss tantalum pentoxide (Ta{sub 2}O{sub 5}) waveguides. A mixture of C{sub 4}F{sub 8} and O{sub 2} gas are used in combination with chromium (Cr) hard mask for this purpose. In this paper, the authors make a detailed investigation of the etch process parameter window. Effects of process parameters such as ICP power, platen power, gas flow, and chamber pressure on etch rate and sidewall slope angle are investigated. Chamber pressure is found to be a particularly important factor, which can be used to tune the sidewall slope angle and so prevent undercut.
A high voltage pulsed power supply for capillary discharge waveguide applications
Abuazoum, S.; Wiggins, S. M.; Issac, R. C.; Welsh, G. H.; Vieux, G.; Jaroszynski, D. A. [Department of Physics, Scottish Universities Physics Alliance, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Ganciu, M. [Low Temperature Plasma Department, National Institute of Lasers, Plasma and Radiation Physics, 077125, Magurele, Bucharest (Romania)
2011-06-15T23:59:59.000Z
We present an all solid-state, high voltage pulsed power supply for inducing stable plasma formation (density {approx}10{sup 18} cm{sup -3}) in gas-filled capillary discharge waveguides. The pulser (pulse duration of 1 {mu}s) is based on transistor switching and wound transmission line transformer technology. For a capillary of length 40 mm and diameter 265 {mu}m and gas backing pressure of 100 mbar, a fast voltage pulse risetime of 95 ns initiates breakdown at 13 kV along the capillary. A peak current of {approx}280 A indicates near complete ionization, and the r.m.s. temporal jitter in the current pulse is only 4 ns. Temporally stable plasma formation is crucial for deploying capillary waveguides as plasma channels in laser-plasma interaction experiments, such as the laser wakefield accelerator.
High-Gradient Tests of the Single-Cell SC Cavity with a Feedback Waveguide
Yakovlev, V.; Solyak, N.; Wu, G.; Ge, M.; Gonin, I.; Khabiboulline, T.; Ozelis, J.; Rowe, A. [Fermilab, Batavia, IL 60510 (United States); Avrakhov, P.; Kanareykin, A. [Euclid TechLabs, LLC, Solon, Ohio 44139 (United States); Rathke, J. [AES, Medford, NY 11763 (United States)
2010-11-04T23:59:59.000Z
Use of a superconducting (SC) traveling-wave accelerating (STWA) structure with a small phase advance per cell, rather than a standing-wave structure, may provide a significant increase in the accelerating gradient in the ILC linac [1]. For the same surface electric and magnetic fields, the STWA achieves an accelerating gradient 1.2 larger than TESLA-like standing-wave cavities. In addition, the STWA allows longer acceleration cavities, reducing the number of gaps between them. However, the STWA structure requires a SC feedback waveguide to return the few hundreds of MW of circulating RF power from the structure output to the structure input. A test single-cell cavity with feedback was designed and manufactured to demonstrate the possibility of proper processing to achieve a high accelerating gradient. The first results of high-gradient tests of a prototype 1.3 GHz single-cell cavity with feedback waveguide will be presented.
An RF Waveguide Distribution System for the ILC Test Accelerator at Fermilab's NML
Nantista, Christopher; Adolphsen, Chris; Bowden, Gordon; Swent, Richard; McKee, Bobby; /SLAC
2007-06-27T23:59:59.000Z
An ILC R&D facility is being constructed in the NML building at Fermilab which, in addition to an injector and beam dump with spectrometer, will contain up to three cryomodules of ILC-type superconducting 9-cell cavities. This linac will be powered by a single klystron. As part of SLAC's contribution to this project, we will provide a distribution network in WR650 waveguide to the various cavity couplers. In addition to commercial waveguide components and circulators and loads, this system will include adjustable tap-offs, and customized hybrids. In one configuration, the circulators will be removed to test pair-wise cancellation of cavity reflections through hybrids. The system will be pressurized with nitrogen to 3 bar absolute to avoid the need for SF{sub 6}. The full distribution system for the first cryomodule will be delivered and installed later this year. We describe the design of the system and completed RF testing.
Metallic nanoparticles grown in the core of femtosecond laser micromachined waveguides
Almeida, J. M. P.; Ferreira, P. H. D.; Mendonça, C. R., E-mail: crmendon@ifsc.usp.br [Instituto de Física de Săo Carlos, Universidade de Săo Paulo—USP, CP 369, Săo Carlos, Sao Paulo 13560-970 Brazil (Brazil); Manzani, D.; Napoli, M.; Ribeiro, S. J. L. [Institute of Chemistry—Săo Paulo State University—UNESP, CP 355, Araraquara, Sao Paulo 14801-970 (Brazil)
2014-05-21T23:59:59.000Z
3D-waveguides containing silver nanoparticles have been fabricated in tungsten lead–pyrophosphate glass by femtosecond laser micromachining. Nucleation and growth of nanoparticles occur in a single step process when high repetition rate laser (MHz) is employed, while an additional annealing is required for the irradiation using kHz laser system. The presence of nanoparticles locally changes the refractive index, and, therefore, the elliptical structures produced by direct laser writing were able to guide light. By increasing the pulse energy applied during the micromachining, the waveguide size increased from 2 to 30??m, while their propagation loss decrease from 1.4 to 0.5?dB/mm at 632.8?nm.
Chen, Yaohui; Gregersen, Niels; Mřrk, Jesper
2015-01-01T23:59:59.000Z
We derive and validate a set of coupled Bloch wave equations for analyzing the reflection and transmission properties of active semiconductor photonic crystal waveguides. In such devices, slow-light propagation can be used to enhance the material gain per unit length, enabling, for example, the realization of short optical amplifiers compatible with photonic integration. The coupled wave analysis is compared to numerical approaches based on the Fourier modal method and a frequency domain finite element technique. The presence of material gain leads to the build-up of a backscattered field, which is interpreted as distributed feedback effects or reflection at passive-active interfaces, depending on the approach taken. For very large material gain values, the band structure of the waveguide is perturbed, and deviations from the simple coupled Bloch wave model are found.
Microwave breakdown for the TE{sub 10} mode in a rectangular waveguide
Malik, Hitendra K.; Aria, Anil K. [Plasma Waves and Particle Acceleration Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi–110 016 (India)] [Plasma Waves and Particle Acceleration Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi–110 016 (India)
2013-08-15T23:59:59.000Z
Microwave breakdown is studied for the lowest order TE{sub 10} mode in a rectangular waveguide with the help of direct variational approach via the continuity equation along with the use of ionisation and attachment frequency. We investigate the role of the ionisation, attachment of electron with neutral gas or air molecules and the diffusion on microwave breakdown threshold in the waveguide filled with air or Ar Gas. We examine the effect of different gases and microwave parameters on the diffusion length and the breakdown threshold of electric field of continuous microwave and pulsed microwave. We also employ numerical approach for obtaining the results and compare them with the ones of variational approach.
Polarization engineering in photonic crystal waveguides for spin-photon entanglers
Andrew B. Young; Arthur Thijssen; Daryl M. Beggs; Petros Androvitsaneas; L. Kuipers; John G. Rarity; Stephen Hughes; Ruth Oulton
2015-07-03T23:59:59.000Z
By performing a full analysis of the projected local density of states (LDOS) in a photonic crystal waveguide, we show that phase plays a crucial role in the symmetry of the light-matter interaction. By considering a quantum dot (QD) spin coupled to a photonic crystal waveguide (PCW) mode, we demonstrate that the light-matter interaction can be asymmetric, leading to unidirectional emission and a deterministic entangled photon source. Further we show that understanding the phase associated with both the LDOS and the QD spin is essential for a range of devices that that can be realised with a QD in a PCW. We also show how quantum entanglement can completely reverse photon propagation direction, and highlight a fundamental breakdown of the semiclassical dipole approximation for describing light-matter interactions in these spin dependent systems.
Usoskin, Ilya G.
-on-insulator waveguides. Digest of the OSA Integrated and Guided-Wave Optics Topical Meeting 8689 (Optical Society
Reactive-coupling-induced normal mode splittings in microdisk resonators coupled to waveguides
Huang Sumei; Agarwal, G. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)
2010-05-15T23:59:59.000Z
We study the optomechanical design introduced by M. Li et al. [Phys. Rev. Lett. 103, 223901 (2009)], which is very effective for investigation of the effects of reactive coupling. We show the normal mode splitting that is due solely to reactive coupling rather than due to dispersive coupling. We suggest feeding the waveguide with a pump field along with a probe field and scanning the output probe for evidence of reactive-coupling-induced normal mode splitting.
Programmably structured plasma waveguide for development of table-top photon and particle sources
Hung, T.-S.; Ho, Y.-C.; Wong, S.-J.; Chen, S.-Y. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Chang, Y.-L. [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Department of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China); Chu, H.-H. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Lin, J.-Y. [Department of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China); Wang, J. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Department of Physics, National Taiwan University, Taipei 106, Taiwan (China)
2012-06-15T23:59:59.000Z
Programmable fabrication of longitudinal spatial structures in an optically preformed plasma waveguide in a gas jet was achieved, by using laser machining with a liquid-crystal spatial light modulator as the pattern mask. Fabrication of periodic structures with a minimal period of 200 {mu}m and density-ramp structures with a minimal slope length of 100 {mu}m was attained. The technique is useful for the optimization of various laser-plasma-based photon and particle sources.
Quantum correlation of path-entangled two-photon states in waveguide arrays with defects
Dou, Yiling; Xu, Lei; Han, Bin; Bo, Fang; Xu, Jingjun; Zhang, Guoquan, E-mail: zhanggq@nankai.edu.cn [The MOE Key Laboratory of Weak Light Nonlinear Photonics, School of Physics and TEDA Applied Physics Institute, Nankai University, Tianjin 300457 (China)] [The MOE Key Laboratory of Weak Light Nonlinear Photonics, School of Physics and TEDA Applied Physics Institute, Nankai University, Tianjin 300457 (China)
2014-04-15T23:59:59.000Z
We study the quantum correlation of path-entangled states of two photons in coupled one-dimensional waveguide arrays with lattice defects. Both off-diagonal and diagonal defects are considered, which show different effects on the quantum correlation of path-entangled two-photon states. Two-photon bunching or anti-bunching effects can be observed and controlled. The two photons are found to have a tendency to bunch at the side lobes with a repulsive off-diagonal defect, and the path-entanglement of the input two-photon state can be preserved during the propagation. We also found that defect modes may play an important role on the two-photon correlation of path-entangled states in the waveguide arrays. Due to the quantum interference effect, intriguing evolution dynamics of the two-photon correlation matrix elements with oscillation frequencies being either twice of or the same as that of a classical light wave, depending on the position of the correlation matrix element, is observed. Our results show that it is possible to manipulate the two-photon correlation properties of path-entangled states in waveguide arrays with lattice defects.
A Kinetic View of Statistical Physics, by Pavel L. Krapivsky, Sidney Redner and Eli Ben-Naim, Cam-
Ben-Naim, Eli
manipulations, the book manages to introduce a multitude of theoretical approaches to the behaviour of nonlinearA Kinetic View of Statistical Physics, by Pavel L. Krapivsky, Sidney Redner and Eli Ben-Naim, Cam structures apparently faithfully mirroring the structure of reality. Classical mechanics and Maxwellian elec
Parameter and state estimation in nonlinear dynamical systems
Creveling, Daniel R.
2008-01-01T23:59:59.000Z
and J. Kurths. Nonlinear dynamical system identi?ca- tionEstimation In Nonlinear Dynamical Systems A dissertationState Estimation In Nonlinear Dynamical Systems by Daniel R.
Block-oriented nonlinear system identification using semidenite programming
Han, Younghee
2012-01-01T23:59:59.000Z
repre- sents a nonlinear dynamical system as a combinationlinear dynamical system and the static nonlinear functionunknown linear dynamical systems G(q) and a static nonlinear
Nonlinear Time Domain Modeling and Simulation of Surface and...
Office of Environmental Management (EM)
Nonlinear Time Domain Modeling and Simulation of Surface and Embedded NPPS Nonlinear Time Domain Modeling and Simulation of Surface and Embedded NPPS Nonlinear Time Domain Modeling...
Non-Linear Seismic Soil Structure Interaction (SSI) Method for...
Office of Environmental Management (EM)
Non-Linear Seismic Soil Structure Interaction (SSI) Method for Developing Non-Linear Seismic SSI Analysis Techniques Non-Linear Seismic Soil Structure Interaction (SSI) Method for...
Ackermann, Mark R. (Albuquerque, NM); McGraw, John T. (Placitas, NM); Zimmer, Peter C. (Albuquerque, NM)
2008-01-15T23:59:59.000Z
A wide field of view telescope having two concave and two convex reflective surfaces, each with an aspheric surface contour, has a flat focal plane array. Each of the primary, secondary, tertiary, and quaternary reflective surfaces are rotationally symmetric about the optical axis. The combination of the reflective surfaces results in a wide field of view in the range of approximately 3.8.degree. to approximately 6.5.degree.. The length of the telescope along the optical axis is approximately equal to or less than the diameter of the largest of the reflective surfaces.
Waveguide detuning caused by transverse magnetic fields on a simulated in-line 6 MV linac
St Aubin, J.; Steciw, S.; Fallone, B. G. [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)
2010-09-15T23:59:59.000Z
Purpose: Due to the close proximity of the linear accelerator (linac) to the magnetic resonance (MR) imager in linac-MR systems, it will be subjected to magnet fringe fields larger than the Earth's magnetic field of 5x10{sup -5} T. Even with passive or active shielding designed to reduce these fields, some magnitude of the magnetic field is still expected to intersect the linac, causing electron deflection and beam loss. This beam loss, resulting from magnetic fields that cannot be eliminated with shielding, can cause a detuning of the waveguide due to excessive heating. The detuning, if significant, could lead to an even further decrease in output above what would be expected strictly from electron deflections caused by an external magnetic field. Thus an investigation of detuning was performed through various simulations. Methods: According to the Lorentz force, the electrons will be deflected away from their straight course to the target, depositing energy as they impact the linac copper waveguide. The deposited energy would lead to a heating and deformation of the copper structure resulting in resonant frequency changes. PARMELA was used to determine the mean energy and fraction of total beam lost in each linac cavity. The energy deposited into the copper waveguide from the beam losses caused by transverse magnetic fields was calculated using the Monte Carlo program DOSRZnrc. From the total energy deposited, the rise in temperature and ultimately the deformation of the structure was estimated. The deformed structure was modeled using the finite element method program COMSOL MULTIPHYSICS to determine the change in cavity resonant frequency. Results: The largest changes in resonant frequency were found in the first two accelerating cavities for each field strength investigated. This was caused by a high electron fluence impacting the waveguide inner structures coupled with their low kinetic energies. At each field strength investigated, the total change in accelerator frequency was less than a manufacturing tolerance of 10 kHz and is thus not expected to have a noticeable effect on accelerator performance. Conclusions: The amount of beam loss caused by magnetic fringe fields for a linac in a linac-MR system depends on the effectiveness of its magnetic shielding. Despite the best efforts to shield the linac from the magnetic fringe fields, some persistent magnetic field is expected which would result in electron beam loss. This investigation showed that the detuning of the waveguide caused by additional electron beam loss in persistent magnetic fields is not a concern.
Nonlinear Processes in Geophysics (2002) 9: 497512 Nonlinear Processes
Paris-Sud XI, Université de
2002-01-01T23:59:59.000Z
function de- scribing the balance of energy for waves under consideration and U(x, t) is the local wind de Pesquisas Espaciais (INPE), CPTEC/INPE, Cachoeira Paulista, SP, 12630-000, Brazil *permanent. To evaluate a quality of any approxima- tion for the 2-D nonlinear energy transfer, a mathematical measure
Input a journal Viewing Journals
Sussex, University of
Journals Contents: Input a journal Viewing Journals Deleting a journal Entering jnl into different period Problems Input a journal 1 Login to Bluqube 2 Select 3 Enter relevant Doc type To select the number of journals you will processing & the total credit value 6 Click on 7 Enter brief description 8
Observability and Controllability of Nonlinear Networks: The Role of Symmetry
Andrew J. Whalen; Sean N. Brennan; Timothy D. Sauer; Steven J. Schiff
2014-10-06T23:59:59.000Z
Observability and controllability are essential concepts to the design of predictive observer models and feedback controllers of networked systems. For example, noncontrollable mathematical models of real systems have subspaces that influence model behavior, but cannot be controlled by an input. Such subspaces can be difficult to determine in complex nonlinear networks. Since almost all of the present theory was developed for linear networks without symmetries, here we present a numerical and group representational framework, to quantify the observability and controllability of nonlinear networks with explicit symmetries that shows the connection between symmetries and nonlinear measures of observability and controllability. We numerically observe and theoretically predict that not all symmetries have the same effect on network observation and control. Our analysis shows that the presence of symmetry in a network may decrease observability and controllability, although networks containing only rotational symmetries remain controllable and observable. These results alter our view of the nature of observability and controllability in complex networks, change our understanding of structural controllability, and affect the design of mathematical models to observe and control such networks.
2008-12-16T23:59:59.000Z
The aim of this paper is to give a survey of some basic theory of semi-infinite programming. .... operations of addition and multiplication by a scalar. We associate ...
2013-11-05T23:59:59.000Z
Approach. ?. Selin Damla Ahipasao?glu the date of receipt and acceptance should be .... which has the minimum volume is a natural choice from both theoretical and ... This problem has important applications in statistics and solving this prob- ...... the SDPT3 algorithm using the CVX platform on MATLAB, which is a classic.
2006-02-28T23:59:59.000Z
Feb 28, 2006 ... AMS 2000 Subject Classification: Primary: ... of free NSO solvers, a possible reason is the lack of a significant library of NSO test functions.
Developments and advances in nonlinear terahertz spectroscopy
Brandt, Nathaniel Curran
2014-01-01T23:59:59.000Z
Nonlinear terahertz (THz) spectroscopy is a rapidly developing field, which is concerned with driving and observing nonlinear material responses in the THz range of the electromagnetic spectrum. In this thesis, I present ...
Mathematics 658 Nonlinear Dynamics and Geometic Mechanics
Bloch, Anthony
Mathematics 658 Nonlinear Dynamics and Geometic Mechanics Instructor: Anthony M. Bloch. Office of ordinary differential equations and dynamical systems, with applications to various mechanical and physical geometry, nonlinear stability theory, Lagrangian and Hamiltonian mechanics, integrable systems, reduction
Optimization Online - Nonlinear Optimization Submissions - 2013
Nonlinear Optimization Submissions - 2013. January 2013. A Framework of Constraint Preserving Update Schemes for Optimization on Stiefel Manifold
Optimization Online - Nonlinear Optimization Submissions - 2012
Nonlinear Optimization Submissions - 2012. January 2012. Systems governed by Differential Equations Optimization Squeeze-and-Breathe Evolutionary Monte ...
Nonlinear Michelson interferometer for improved quantum metrology
Alfredo Luis; Ángel Rivas
2015-04-21T23:59:59.000Z
We examine nonlinear quantum detection via a Michelson interferometer embedded in a gas with Kerr nonlinearity. The interferometer is illuminated by pulses of classical light. This strategy combines the robustness against practical imperfections of classical light with the improvement provided by nonlinear detection. Regarding ultimate quantum limits, we stress that, as a difference with linear schemes, the nonlinearity introduces pulse duration as a new variable into play along with the energy resources.
ĂĄ Risa-R-411 Nonlinear Finite Element Analysis of Concrete Structures Niels Saabye Ottosen RisĂ¸ | other IAEA P. 0. Box 100 A-1400, Vienna, Austria #12;RISĂ?-R-411 NONLINEAR FINITE ELEMENT ANALYSIS OF CONCRETE STRUCTURES Niels Saabye Ottosen Abstract. This report deals with nonlinear finite element analy
LANGUAGE LEARNING AND NONLINEAR DYNAMICAL SYSTEMS
Andrews, Mark W.
LANGUAGE LEARNING AND NONLINEAR DYNAMICAL SYSTEMS A Dissertation Presented to the Faculty LEARNING AND NONLINEAR DYNAMICAL SYSTEMS Mark William Andrews, Ph.D. Cornell University 2003 The thesis be provided by an better appreciation of the capacities of nonlinear dynamical systems to learn, rep- resent
Jun, Kawai
2010-01-01T23:59:59.000Z
-Ray Waveguide Using Fresnel Diffraction Yusuke MORIKAWA and Jun KAWAI #12;#12;41 145 X Adv. X-Ray. Chem. Anal., Japan 41, pp.145-150 (2010) 606-8501 X Theoretical Analysis of X-Ray Waveguide Using Fresnel Diffraction symmetrical pattern. We regard it as a slit and calculated the Fresnel diffraction. We find
Paris-Sud XI, Université de
Source localisation in deep water using waveguide invariant distribution Julien Bonnel1, Barbara. For deep water waveguides, the invariant varies and no straightforward methods exist to take benefit of it. Indeed, in deep water many modes contributes to the acoustic intensity and the invariant depends
Hamilton, C.
1995-02-01T23:59:59.000Z
Views of the Solar System has been created as an educational tour of the solar system. It contains images and information about the Sun, planets, moons, asteroids and comets found within the solar system. The image processing for many of the images was done by the author. This tour uses hypertext to allow space travel by simply clicking on a desired planet. This causes information and images about the planet to appear on screen. While on a planet page, hyperlinks travel to pages about the moons and other relevant available resources. Unusual terms are linked to and defined in the Glossary page. Statistical information of the planets and satellites can be browsed through lists sorted by name, radius and distance. History of Space Exploration contains information about rocket history, early astronauts, space missions, spacecraft and detailed chronology tables of space exploration. The Table of Contents page has links to all of the various pages within Views Of the Solar System.
Views of wireless network systems.
Young, William Frederick; Duggan, David Patrick
2003-10-01T23:59:59.000Z
Wireless networking is becoming a common element of industrial, corporate, and home networks. Commercial wireless network systems have become reliable, while the cost of these solutions has become more affordable than equivalent wired network solutions. The security risks of wireless systems are higher than wired and have not been studied in depth. This report starts to bring together information on wireless architectures and their connection to wired networks. We detail information contained on the many different views of a wireless network system. The method of using multiple views of a system to assist in the determination of vulnerabilities comes from the Information Design Assurance Red Team (IDART{trademark}) Methodology of system analysis developed at Sandia National Laboratories.
For current viewing resistor loads
Lyons, Gregory R. (Tijeras, NM); Hass, Jay B. (Lee's Summit, MO)
2011-04-19T23:59:59.000Z
The invention comprises a terminal unit for a flat cable comprising a BNC-PCB connector having a pin for electrically contacting one or more conducting elements of a flat cable, and a current viewing resistor having an opening through which the pin extends and having a resistor face that abuts a connector face of the BNC-PCB connector, wherein the device is a terminal unit for the flat cable.
Thomas, Sunil; Solis, Javier; Biju, P R; Unnikrishnan, N V
2015-01-01T23:59:59.000Z
Low loss, optical channel waveguides have been successfully produced by high repetition rate, femtosecond laser inscription in a Li-Zn fluoroborate glass (64.9B2O3 + 25Li2O + 10ZnF2 + 0.1Er2O3). High quality waveguides were produced at 500 kHz, 1 MHz and 2 MHz laser repetition rates, showing a refractive index contrast in the range of 3-6 x 10-3 depending on various fluences. Dependence of experimental parameters such as average laser power, pulse repetition rate and writing speed on the properties of fabricated waveguides has been discussed. The comparison of optical and compositional characterization techniques evidences an enrichment of B and Zn in the guiding region, while F migrates to the heat diffused region of the written structure.
The Effect of Evanescent Modes and Chaos on Deterministic Scattering in Electron Waveguides
G. B. Akguc; L. E. Reichl
2000-12-12T23:59:59.000Z
Statistical properties of Wigner delay times and the effect of evanescent modes on the deterministic scattering of an electron matter wave from a classically chaotic 2-d electron waveguide are studied for the case of 2, 6, and 16 propagating modes. Deterministic reaction matrix theory for this system is generalized to include the effect of evanescent modes on the scattering process. Inclusion of evanescent modes can change the positions of resonance poles in the complex energy plane and can delay electron scattering, particularly at energies where new channels open. The statistical properties of the Wigner delay times for the deterministic scattering process are compared to the predictions of random reaction matrix theory.
Restricted thermalization for two interacting atoms in a multimode harmonic waveguide
Yurovsky, V. A.; Olshanii, M. [School of Chemistry, Tel Aviv University, IL-69978 Tel Aviv (Israel); Department of Physics, University of Massachusetts Boston, Boston, Massachusetts 02125 (United States)
2010-04-15T23:59:59.000Z
In this article, we study the thermalizability of a system consisting of two atoms in a circular, transversely harmonic waveguide in the multimode regime. While showing some signatures of quantum-chaotic behavior, the system fails to reach a thermal equilibrium in a relaxation from an initial state, even when the interaction between the atoms is infinitely strong. We relate this phenomenon to the previously addressed unattainability of a complete quantum chaos in the Seba billiard [P. Seba, Phys. Rev. Lett. 64, 1855 (1990)], and we conjecture the absence of a complete thermalization to be a generic property of integrable quantum systems perturbed by a nonintegrable but well-localized perturbation.
Ultracold-atom collisions in atomic waveguides : A two-channel analysis
Tom Kristensen; Ludovic Pricoupenko
2015-04-16T23:59:59.000Z
Low dimensional behavior of two ultra-cold atoms trapped in two-and one-dimensional waveguides is investigated in the vicinity of a magnetic Feshbach resonance. A quantitative two-channel model for the Feshbach mechanism is used allowing an exhaustive analysis of low-dimensional resonant scattering behavior and of the confinement induced bound states. The role of the different parameters of the resonance is depicted in this context. Results are compared with the ones of the zero-range approach. The relevance of the effective range approximation in low dimensions is studied. Examples of known resonances are used to illustrate the bound state properties.
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
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.
Bandwidth Studies on a 1.4 m Long Multimode Polymer Spiral Waveguide
Chen, Jian; Bamiedakis, Nikos; Penty, Richard V.; White, Ian H.
2014-07-03T23:59:59.000Z
. The experimental set-up is shown in Fig. 1a and comprises an 850 nm vertical-cavity surface-emitting laser (VCSEL) (bandwidth of ~ 25 GHz) [3], the waveguide sample, a photodiode (bandwidth of ~30 GHz) and a variable optical attenuator (VOA). The VCSEL is butt... for VCSEL fabrication and EPSRC for supporting the work. 5. References: [1] N. Bamiedakis et al, IEEE Journal of Quantum Electronics, vol. 45, no. 4, pp. 415–424, 2009. [2] N. Bamiedakis et al, IEEE Transactions on Components, Packaging and Manufacturing...
Wilson, Joshua L [ORNL
2008-09-01T23:59:59.000Z
A new class of accelerating structures employing a uniformly twisted waveguide is investigated. Twisted waveguides of various cross-sectional geometries are considered and analyzed. It is shown that such a twisted waveguide can support waves that travel at a speed slower than the speed of light c. The slow-wave properties of twisted structures are of interest because these slow-wave electromagnetic fields can be used in applications such as electron traveling wave tubes and linear particle accelerators. Since there is no exact closed form solution for the electromagnetic fields within a twisted waveguide or cavity, several previously proposed approximate methods are examined, and more effcient approaches are developed. It is found that the existing perturbation theory methods yield adequate results for slowly twisted structures; however, our efforts here are geared toward analyzing rapidly twisted structures using modifed finite difference methods specially suited for twisted structures. Although the method can handle general twisted structures, three particular cross sections are selected as representative cases for careful analysis. First, a slowly twisted rectangular cavity is analyzed as a reference case. This is because its shape is simple and perturbation theory already gives a good approximate solution for such slow twists rates. Secondly, a symmetrically notched circular cross section is investigated, since its longitudinal cross section is comparable to the well known disk-loaded cavity (used in many practical accelerator designs, including SLAC). Finally, a "dumbbell" shaped cross section is analyzed because of its similarity to the well-known TESLA-type accelerating cavity, which is of great importance because of its wide acceptance as a superconducting cavity. To validate the results of the developed theory and our extensive simulations, the newly developed numerical models are compared to commercial codes. Also, several prototypes are developed employing the three basic shapes discussed previously. Bench measurements are performed on the prototype cavities to evaluate dispersion by measuring the field distribution along these cavities. The measurement results are compared to the simulations and theoretical results, and good agreement is shown. Once validated, the developed models are used to design twisted accelerating structures with specific phase velocities and good accelerating performance.
K. Thyagarajan; R. Das; O. Alibart; M. de Micheli; D. B. Ostrowsky; S. Tanzilli
2009-04-11T23:59:59.000Z
In this paper we show that by suitably tailoring the dispersion characteristics of a Bragg reflection waveguide (BRW) mode, it is possible to achieve efficient photon pair generation over a large pump bandwidth while maintaining narrow signal bandwidth. The structure proposed consists of a high index core BRW with a periodically poled GaN core and periodically stratified cladding made up of alternate layers of $Al_{0.02}Ga_{0.98}N$ and $Al_{0.45}Ga_{0.55}N$. Such photon-pair generators should find applications in realizing compact and stable sources for quantum information processing.
Design and Experimental Characterization of an Erbium Doped GaN Waveguide
Wang, Qian
2012-05-31T23:59:59.000Z
temperatures as compared to other semiconductor host materials such as Si and GaAs. 1540nm optical emission in Er- doped waveguide has also been demonstrated using a 365nm light emitting diode as the optical pumping source. UV pumping above the GaN bandgap....9 eV In Table 2 - 1, GaN is the semiconductor material with the largest bandgap (SiO2 is not a semiconductor), which has proven to be an accomplished host of erbium, with reports of fabrication of light- emitting diodes operating in the visible...
T-junction waveguide-based combining high power microwave beams
Zhang Qiang; Yuan Chengwei; Liu Lie [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)
2011-08-15T23:59:59.000Z
Waveguide-based combining microwave beams is an attractive technique for enhancing the output capacities of narrow-band high power microwave devices. A specific T-junction combiner is designed for combining the X/X band microwave beams, and the detailed combining method and experimental results are presented. In the experiments, two microwave sources which can generate gigawatt level microwaves are driven by a single accelerator simultaneously, and their operation frequencies are 9.41 and 9.60 GHz, respectively. The two microwave beams with durations of about 35 ns have been successfully combined, and no breakdown phenomenon occurs.
Condition assessment of nonlinear processes
Hively, Lee M. (Philadelphia, TN); Gailey, Paul C. (Athens, OH); Protopopescu, Vladimir A. (Knoxville, TN)
2002-01-01T23:59:59.000Z
There is presented a reliable technique for measuring condition change in nonlinear data such as brain waves. The nonlinear data is filtered and discretized into windowed data sets. The system dynamics within each data set is represented by a sequence of connected phase-space points, and for each data set a distribution function is derived. New metrics are introduced that evaluate the distance between distribution functions. The metrics are properly renormalized to provide robust and sensitive relative measures of condition change. As an example, these measures can be used on EEG data, to provide timely discrimination between normal, preseizure, seizure, and post-seizure states in epileptic patients. Apparatus utilizing hardware or software to perform the method and provide an indicative output is also disclosed.
The Equal Weight View, Agreement, and Commutativity
Buckler, Rose
2011-11-23T23:59:59.000Z
This paper investigates Elga’s (2007) Equal Weight View (EWV) and its consequences when understood as a view requiring epistemic peers to ‘split the difference’ following disagreement. The traditional disagreement debate ...
California's Energy Future - The View to 2050
2011-01-01T23:59:59.000Z
Summit on America’s Energy Future (2008), http://www.natural gas. California’s Energy Future - The View to 2050supply California’ s Energy Future - The View to 2050 and
Nonlinear effects in kinetic resolutions
Johnson, Derrell W.
1999-01-01T23:59:59.000Z
~TRIC AMPLIFICATION IN THE JACOBSEN HKR: THE POSSIBLE ITERATIVE ENHANCE~ OF OPTICAL ACTIVITY 35 Using Jacobsen HKR Nonlinear Effects to Demonstrate the Potendal Generation of Optical Activity from "Racemic" Styrene Oxide The Synthetic Conversion of Styrene Oxide... to 1-Phenyl-1, 2-Diaminoethane. Generation of 10% ee S-2 from 10% ee (S)-1-Phenyl-1, 2-Diaminoethane Optimized Amplification Condidons and Degree of Amplification for HKR Reactions with Styrene Oxide and 10% ee S-2. 37 39 43 VI CONCLUSIONS VII...
ISSN 2167-5163 View Publications
Waldschmidt, Michel
ISSN 2167-5163 View Publications View Author/Related Publications View Reviews Refine Search Co: 180085 Earliest Indexed Publication: 1970 Total Publications: 176 Total Author/Related Publications: 189 Chen Publications (by number in area) Associative rings and algebras Dynamical systems and ergodic
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AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) |govInstrumentsmfrirtA Journey Inside the Complex(MARSSIM) SiteOrganization OverviewEMS20152 -PanoramicrunParaView
Giden, I. H., E-mail: igiden@etu.edu.tr; Yilmaz, D.; Turduev, M.; Kurt, H. [Nanophotonics Research Laboratory, Department of Electrical and Electronics Engineering, TOBB University of Economics and Technology, Ankara 06560 (Turkey); Çolak, E. [Electrical and Electronics Engineering Department, Ankara University, Gölbasi, Ankara 06830 (Turkey); Ozbay, E. [Department of Electrical and Electronics Engineering, Bilkent University, Bilkent, Ankara 06800 (Turkey)
2014-01-20T23:59:59.000Z
To provide asymmetric propagation of light, we propose a graded index photonic crystal (GRIN PC) based waveguide configuration that is formed by introducing line and point defects as well as intentional perturbations inside the structure. The designed system utilizes isotropic materials and is purely reciprocal, linear, and time-independent, since neither magneto-optical materials are used nor time-reversal symmetry is broken. The numerical results show that the proposed scheme based on the spatial-inversion symmetry breaking has different forward (with a peak value of 49.8%) and backward transmissions (4.11% at most) as well as relatively small round-trip transmission (at most 7.11%) in a large operational bandwidth of 52.6?nm. The signal contrast ratio of the designed configuration is above 0.80 in the telecom wavelengths of 1523.5–1576.1?nm. An experimental measurement is also conducted in the microwave regime: A strong asymmetric propagation characteristic is observed within the frequency interval of 12.8 GHz–13.3?GHz. The numerical and experimental results confirm the asymmetric transmission behavior of the proposed GRIN PC waveguide.
Martinez, Jennifer S. (Santa Fe, NM); Swanson, Basil I. (Los Alamos, NM); Shively, John E. (Arcadia, CA); Li, Lin (Monrovia, CA)
2009-06-02T23:59:59.000Z
An assay element is described including recognition ligands adapted for binding to carcinoembryonic antigen (CEA) bound to a film on a single mode planar optical waveguide, the film from the group of a membrane, a polymerized bilayer membrane, and a self-assembled monolayer containing polyethylene glycol or polypropylene glycol groups therein and an assay process for detecting the presence of CEA is described including injecting a possible CEA-containing sample into a sensor cell including the assay element, maintaining the sample within the sensor cell for time sufficient for binding to occur between CEA present within the sample and the recognition ligands, injecting a solution including a reporter ligand into the sensor cell; and, interrogating the sample within the sensor cell with excitation light from the waveguide, the excitation light provided by an evanescent field of the single mode penetrating into the biological target-containing sample to a distance of less than about 200 nanometers from the waveguide thereby exciting any bound reporter ligand within a distance of less than about 200 nanometers from the waveguide and resulting in a detectable signal.
Southern California, University of
Observation of coupled plasmon-polariton modes of plasmon waveguides for electromagnetic energy the influence of optical near-field interactions on the dipole surface plasmon resonance of Au nanoparticles, the resonance energies of the collective plasmon-polariton modes are determined for longitudinal and transverse
Luryi, Serge
to the case when the core material is a semiconductor with optical gain. A number of devices are discussedJOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 24, NO. 3, MARCH 2006 1513 Modal Control in Semiconductor-layer optical waveguide on the polarization properties of propagating radiation. Particular attention is paid
Planar waveguide obtained by burying a Ge22As20Se58 fiber in As2S3 glass
Paris-Sud XI, Université de
Planar waveguide obtained by burying a Ge22As20Se58 fiber in As2S3 glass Quentin Coulombier glasses. Two highly mature chalcogenide glasses are used for these experiments. GASIR glass from Umicore IR Glass, Olen, Belgium, with the composition of Ge22As20Se58 is used to draw fibers
Heller, Eric
Mid-Infrared Spectrometer Using Opto-Nanofluidic Slot-Waveguide for Label-Free On-Chip Chemical an engineered nanofluidic channel consisting of a Si-liquid-Si slot- structure. Utilizing the large refractive-IR lightwave can be efficiently guided and confined within a nanofluidic capillary (100 nm wide). The optical
is essential for building future large-scale optical integrated circuits. Photonic crystal waveguides offer Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185 S. G. Johnson and J. D. Joannopoulos Department of light.1 If the line defect is properly designed, the resulting guiding mode falls within a photonic
Stancil, Daniel D.
-to-design wireless net- works with better coverage is to use heating, ventilation, and air conditioning (HVAC) ductsDesign of an Overmoded-Waveguide Directional Antenna for Use in In-Building Ventilation Duct ventilation ducts. We obtain experimentally the element size and spacing of a reflector and driven element
Graphene Nanobubble: A New Optical Nonlinear Material
Bao, Qiaoliang; Xiang, Yuanjiang; Zhang, Kai; Li, Shaojuan; Jiang, Xiaofang; Xu, Qing-Hua; Loh, Kian Ping; Venkatesan, T
2015-01-01T23:59:59.000Z
Graphene is a rising star in nonlinear optics due to its saturable absorption and giant Kerr nonlinearity, these properties are useful in digital optics based on optical nonlinear devices. However, practical applications require large optical nonlinearities and these are inherently limited by the interaction length of atomically thin graphene. Here, we demonstrate optical bistability in a Fabry Perot cavity containing monolayer and bilayer graphene which have been restructured to form nanobubbles. We find that graphene nanobubble can act as a new type of optical nonlinear media due to its vertical side wall as well as added curvature, which enable strong non linear dispersive effects leading to a large optically induced phase change. Unlike thermally induced bistability, the all optical switching between two transmission states happens within a time scale of tens of nanoseconds. Nanobubble based optical devices with intrinsic optical nonlinearity help to overcome the optical path length limitation of atomical...
Better Buildings Network View | March 2015 | Department of Energy
Better Buildings Network View | March 2015 Better Buildings Network View | March 2015 The Better Buildings Network View monthly newsletter from the U.S. Department of Energy's...
The Better Buildings Neighborhood View -- December 2013 | Department...
Office of Environmental Management (EM)
The Better Buildings Neighborhood View -- December 2013 The Better Buildings Neighborhood View -- December 2013 The Better Buildings Neighborhood View monthly newsletter from the...
Nonlinear Control of Delay and PDE Systems
Bekiaris-Liberis, Nikolaos
delay systems, IEEE Transactions on Automatic Control, 56 (lag systems, IEEE Transactions on Automatic Control, 31 (nonlinear systems, IEEE Transactions on Automatic Control,
Single-ion nonlinear mechanical oscillator
Akerman, N.; Kotler, S.; Glickman, Y.; Dallal, Y.; Keselman, A.; Ozeri, R. [Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100 (Israel)
2010-12-15T23:59:59.000Z
We study the steady-state motion of a single trapped ion oscillator driven to the nonlinear regime. Damping is achieved via Doppler laser cooling. The ion motion is found to be well described by the Duffing oscillator model with an additional nonlinear damping term. We demonstrate here the unique ability of tuning both the linear as well as the nonlinear damping coefficients by controlling the laser-cooling parameters. Our observations pave the way for the investigation of nonlinear dynamics on the quantum-to-classical interface as well as mechanical noise squeezing in laser-cooling dynamics.
Sandia National Laboratories: Careers: Special Programs: Nonlinear...
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Nonlinear Mechanics and Dynamics Summer Research Institute FEA modeling simulation A test specimen for measuring dissipation across a lap joint under different loading environments...
Engineering Giant Nonlinearities in Quantum Nanosystems
Kurt Jacobs; Andrew Landahl
2009-08-06T23:59:59.000Z
We describe a method to engineer giant nonlinearities in, and probes to measure nonlinear observables of, mesoscopic quantum resonators. This involves tailoring the Hamiltonian of a simple auxiliary system perturbatively coupled to the resonator, and has the potential to engineer a wide range of nonlinearities to high accuracy. We give a number of explicit examples, including a readily realizable two-qubit auxiliary system that creates an x^4 potential and a Chi^(3) (Kerr) nonlinearity, valid to fifth-order in the perturbative coupling.
Linear conic optimization for nonlinear optimal control
Didier Henrion
2014-07-07T23:59:59.000Z
Jul 7, 2014 ... Abstract: Infinite-dimensional linear conic formulations are described for nonlinear optimal control problems. The primal linear problem consists ...
Nonlinear conformation of secondary protein folding
Januar, M; Handoko, L T
2012-01-01T23:59:59.000Z
A model to describe the mechanism of conformational dynamics in secondary protein based on matter interactions is proposed. The approach deploys the lagrangian method by imposing certain symmetry breaking. The protein backbone is initially assumed to be nonlinear and represented by the Sine-Gordon equation, while the nonlinear external bosonic sources is represented by $\\phi^4$ interaction. It is argued that the nonlinear source induces the folding pathway in a different way than the previous work with initially linear backbone. Also, the nonlinearity of protein backbone decreases the folding speed.
Detonator comprising a nonlinear transmission line
Elizondo-Decanini, Juan M
2014-12-30T23:59:59.000Z
Detonators are described herein. In a general embodiment, the detonator includes a nonlinear transmission line that has a variable capacitance. Capacitance of the nonlinear transmission line is a function of voltage on the nonlinear transmission line. The nonlinear transmission line receives a voltage pulse from a voltage source and compresses the voltage pulse to generate a trigger signal. Compressing the voltage pulse includes increasing amplitude of the voltage pulse and decreasing length of the voltage pulse in time. An igniter receives the trigger signal and detonates an explosive responsive to receipt of the trigger signal.
Optimization Online - Nonlinear Model Predictive Control via ...
M. J. Tenny
2002-08-15T23:59:59.000Z
Aug 15, 2002 ... Nonlinear Model Predictive Control via Feasibility-Perturbed Sequential Quadratic Programming. M. J. Tenny (tenny ***at*** bevo.che.wisc.edu)
AN INDUCTION THEOREM AND NONLINEAR REGULARITY ...
2014-10-11T23:59:59.000Z
Federation University Australia (pqkhanhus@gmail.com). ‡Centre for ... majority of researchers focus on the particular case of “power nonlinearities” when µ.
Optimization Online - Nonlinear Optimization Submissions - 2015
Nonlinear Optimization Submissions - 2015. January 2015. On iteratively reweighted Algorithms for Non-smooth Non-convex Optimization in Computer Vision
On Test Sets for Nonlinear Integer Maximization
2008-02-05T23:59:59.000Z
On Test Sets for Nonlinear. Integer Maximization. July 2007; revised February 2008. Jon Leea, Shmuel Onnb, Robert Weismantelc a IBM T.J. Watson Research
Nonlinear and magic ponderomotive spectroscopy
Moore, Kaitlin
2015-01-01T23:59:59.000Z
In ponderomotive spectroscopy an amplitude-modulated optical standing wave is employed to probe Rydberg-atom transitions, utilizing a ponderomotive rather than a dipole-field interaction. Here, we engage nonlinearities in the modulation to drive dipole-forbidden transitions up to the fifth order. We reach transition frequencies approaching the sub-THz regime. We also demonstrate magic-wavelength conditions, which result in symmetric spectral lines with a Fourier-limited feature at the line center. Applicability to precision measurement is discussed.
Nonlinear structural crack growth monitoring
Welch, Donald E. (Oak Ridge, TN); Hively, Lee M. (Philadelphia, TN); Holdaway, Ray F. (Clinton, TN)
2002-01-01T23:59:59.000Z
A method and apparatus are provided for the detection, through nonlinear manipulation of data, of an indicator of imminent failure due to crack growth in structural elements. The method is a process of determining energy consumption due to crack growth and correlating the energy consumption with physical phenomena indicative of a failure event. The apparatus includes sensors for sensing physical data factors, processors or the like for computing a relationship between the physical data factors and phenomena indicative of the failure event, and apparatus for providing notification of the characteristics and extent of such phenomena.
A model of nonlinear electrodynamics
S. I. Kruglov
2014-12-02T23:59:59.000Z
A new model of nonlinear electrodynamics with two parameters is investigated. We also consider a model with one dimensional parameter. It was shown that the electric field of a point-like charge is not singular at the origin and there is the finiteness of the static electric energy of point-like charged particle. We obtain the canonical and symmetrical Belinfante energy-momentum tensors and dilatation currents. It is demonstrated that the dilatation symmetry and dual symmetry are broken in the models suggested. We have calculated the static electric energy of point-like particles.
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AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5(Million Cubic Feet) Oregon (Including Vehicle Fuel) (Million Cubic Feet) Natural Gas Delivered toNew6ALCATOR C-MODPlasmaof Dec. 31 Datato
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5(Million Cubic Feet) Oregon (Including Vehicle Fuel) (Million Cubic Feet) Natural Gas Delivered toNew6ALCATOR C-MODPlasmaof Dec. 31 Datatodamping of
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5(Million Cubic Feet) Oregon (Including Vehicle Fuel) (Million Cubic Feet) Natural Gas Delivered toNew6ALCATOR C-MODPlasmaof Dec. 31 Datatodamping
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5(Million Cubic Feet) Oregon (Including Vehicle Fuel) (Million Cubic Feet) Natural Gas Delivered toNew6ALCATOR C-MODPlasmaof Dec. 31
Butcher, Eric A.
2005-01-01T23:59:59.000Z
Nonlinear Dynamics (2005) 41: 237273 c Springer 2005 Order Reduction of Parametrically Excited Nonlinear Systems: Techniques and Applications S. C. SINHA1, , SANGRAM REDKAR1 , VENKATESH DESHMUKH2 , and ERIC A. BUTCHER2 1Nonlinear Systems Research Laboratory, Department of Mechanical Engineering, Auburn
Ding-jiang Huang; Qin-min Yang; Shui-geng Zhou
2013-12-18T23:59:59.000Z
Reduction operators, i.e. the operators of nonclassical (or conditional) symmetry of a class of variable coefficient nonlinear wave equations with power nonlinearities is investigated within the framework of singular reduction operator. A classification of regular reduction operators is performedwith respect to generalized extended equivalence groups. Exact solutions of some nonlinear wave model which are invariant under certain reduction operators are also constructed.
Nonlinear Spectroscopy of Trapped Ions
Frank Schlawin; Manuel Gessner; Shaul Mukamel; Andreas Buchleitner
2014-10-07T23:59:59.000Z
Nonlinear spectroscopy employs a series of laser pulses to interrogate dynamics in large interacting many-body systems, and has become a highly successful method for experiments in chemical physics. Current quantum optical experiments approach system sizes and levels of complexity which require the development of efficient techniques to assess spectral and dynamical features with scalable experimental overhead. However, established methods from optical spectroscopy of macroscopic ensembles cannot be applied straightforwardly to few-atom systems. Based on the ideas proposed in [M. Gessner et al. New J. Phys. 16 092001 (2014)], we develop a diagrammatic approach to construct nonlinear measurement protocols for controlled quantum systems and discuss experimental implementations with trapped ion technology in detail. These methods in combination with distinct features of ultra-cold matter systems allow us to monitor and analyze excitation dynamics in both the electronic and vibrational degrees of freedom. They are independent of system size, and can therefore reliably probe systems where, e.g., quantum state tomography becomes prohibitively expensive. We propose signals that can probe steady state currents, detect the influence of anharmonicities on phonon transport, and identify signatures of chaotic dynamics near a quantum phase transition in an Ising-type spin chain.
Computational Reality XIII Non-linear regression
Berlin,Technische Universität
Computational Reality XIII Non-linear regression Inverse analysis II B. Emek Abali @ LKM - TU Berlin Abstract Linear regression to fit and determine parameters, shown in the last tutorial, is quite useful and widely implemented, however, there are material models where parameters are coupled non-linearly
Nonlinear Peltier effect in semiconductors Mona Zebarjadia
Nonlinear Peltier effect in semiconductors Mona Zebarjadia Department of Electrical Engineering; published online 18 September 2007 Nonlinear Peltier coefficient of a doped InGaAs semiconductor for single parabolic band semiconductors assuming a shifted Fermi-Dirac electronic distribution under
Nonlinear Lattice Waves in Random Potentials
Sergej Flach
2014-09-10T23:59:59.000Z
Localization of waves by disorder is a fundamental physical problem encompassing a diverse spectrum of theoretical, experimental and numerical studies in the context of metal-insulator transition, quantum Hall effect, light propagation in photonic crystals, and dynamics of ultra-cold atoms in optical arrays. Large intensity light can induce nonlinear response, ultracold atomic gases can be tuned into an interacting regime, which leads again to nonlinear wave equations on a mean field level. The interplay between disorder and nonlinearity, their localizing and delocalizing effects is currently an intriguing and challenging issue in the field. We will discuss recent advances in the dynamics of nonlinear lattice waves in random potentials. In the absence of nonlinear terms in the wave equations, Anderson localization is leading to a halt of wave packet spreading. Nonlinearity couples localized eigenstates and, potentially, enables spreading and destruction of Anderson localization due to nonintegrability, chaos and decoherence. The spreading process is characterized by universal subdiffusive laws due to nonlinear diffusion. We review extensive computational studies for one- and two-dimensional systems with tunable nonlinearity power. We also briefly discuss extensions to other cases where the linear wave equation features localization: Aubry-Andre localization with quasiperiodic potentials, Wannier-Stark localization with dc fields, and dynamical localization in momentum space with kicked rotors.
PROCESS CONTROLLABILITY ANALYSIS USING LINEAR AND NONLINEAR
Skogestad, Sigurd
PROCESS CONTROLLABILITY ANALYSIS USING LINEAR AND NONLINEAR OPTIMISATION Samara D. Chenery October linear and nonlinear dynamic optimisation techniques. For the linear case an optimal control problem is formulated to assess the best achievable performance for the set of linear time invariant (LTI) controllers
Nonlinear Radon and Fourier Transforms Franois Rouvire
Vallette, Bruno
Nonlinear Radon and Fourier Transforms François Rouvičre Université de Nice Laboratoire Dieudonné, of the clas- sical Radon transform on hyperplanes. A function f on Rn can be reconstructed from nonlinear Radon transforms, obtained by integrating f and a ...nite num- ber of multiples x f over a family
Nonlinear principal component analysis by neural networks
Hsieh, William
Nonlinear principal component analysis by neural networks William W. Hsieh Oceanography oversimplification of the datasets being analyzed. The advent of neural network (NN) models, a class of powerful by a neural net- work model which nonlinearly generalizes the classical principal component analysis (PCA
Nonlinear principal component analysis by neural networks
Hsieh, William
Nonlinear principal component analysis by neural networks William W. Hsieh Oceanography a potential oversimplification of the datasets being analyzed. The advent of neural network (NN) models by a neural net work model which nonlinearly generalizes the classical principal component analysis (PCA
Jin, Cheng
We investigate the efficient generation of low-divergence high-order harmonics driven by waveform-optimized laser pulses in a gas-filled hollow waveguide. The drive waveform is obtained by synthesizing two-color laser ...
Chen, Tianrun
2009-01-01T23:59:59.000Z
When an acoustic field propagates through a multimodal waveguide, the effect of variations in medium properties induced by 3D random inhomogeneities accumulates by multiple forward scattering over range. This causes ...
A high thermal conductivity waveguide window for use in a free electron laser
T. Elliott; V. Nguyen; L. Phillips; J. Preble (Jefferson Lab); T. Schultheiss; V. Christina; M. Cole; J. Rathke (Northrop Grumman Corp.)
1999-04-01T23:59:59.000Z
Design, analysis, and testing of a waveguide window with a goal of propagating greater than 100 kW average power operating at 1500 Mhz has been performed. This is made possible by the favorable material properties of beryllia (BeO). Brazing the window to a soft copper frame and then brazing the frame to a KOVAR flange provides the vacuum seal. RF analysis combined with thermal/structural analysis shows the benefits of the material. The KOVAR flange with a CTE, coefficient of thermal expansion, that matches that of BeO enables a strong braze joint. RF testing to 35 kW has been successful. The basics of this design can be expanded to applications with lower frequencies and higher average power. A paper similar to this was presented at LINAC 98.
All-dielectric periodic terajet waveguide using an array of coupled cuboids
Minin, I V; Pacheco-Peńa, V; Beruete, M
2015-01-01T23:59:59.000Z
In this paper, the recently proposed technique to produce photonic jets (terajets at THz frequencies) using 3D dielectric cuboids is applied in the design of mesoscale cuboid-chain waveguide. The chains are basically designed with several dielectric cubes with dimensions {\\lambda}0 along the x, y and z axes placed periodically along the axial z-axis and separated by an air-gap. Based on this, a systematic study of the focusing properties and wave guiding of this chain is performed when the air-gap between the dielectric cubes is changed from 0.25{\\lambda}0 to 2.5{\\lambda}0 with the best performance achieved with the latter design. The numerical results of focusing and transport properties are carried out using Finite Integration Technique. The results here presented may be scaled to any frequency ranges such as millimeter, sub-millimeter or optical frequencies.
S. M. Wang; Q. Q. Cheng; Y. X. Gong; P. Xu; L. Li; T. Li; S. N. Zhu
2014-08-09T23:59:59.000Z
It has been proved that surface plasmon polariton (SPP) can well conserve and transmit the quantum nature of entangled photons. Therefore, further utilization and manipulation of such quantum nature of SPP in a plasmonic chip will be the next task for scientists in this field. In quantum logic circuits, the controlled-NOT (CNOT) gate is the key building block. Here, we implement the first plasmonic quantum CNOT gate with several-micrometer footprint by utilizing a single polarization-dependent beam-splitter (PDBS) fabricated on the dielectric-loaded SPP waveguide (DLSPPW). The quantum logic function of the CNOT gate is characterized by the truth table with an average fidelity of. Its entangling ability to transform a separable state into an entangled state is demonstrated with the visibilities of and for non-orthogonal bases. The DLSPPW based CNOT gate is considered to have good integratability and scalability, which will pave a new way for quantum information science.
Quantum simulation of a triatomic chemical reaction with ultracold atoms on a waveguide
E. Torrontegui; A. Ruschhaupt; D. Guéry-Odelin; J. G. Muga
2011-02-23T23:59:59.000Z
We study the scaling and coordinate transformation to physically simulate quantum three-body collinear chemical reactions of the type A+BC $\\rightarrow$ AB+C by the motion of single ultracold atoms or a weakly interacting Bose-Einstein condensate on an $L$-shaped waveguide. As an example we show that the parameters to model the reaction F+HH $\\to$ H+HF with lithium are at reach with current technology. This mapping provides also an inverse scattering tool to find an unknown potential, and a way to transfer the knowledge on molecular reaction dynamics to design beam splitters for cold atoms with control of the channel outcome and vibrational excitation.
Sakai, Osamu; Maeda, Jun; Shimomura, Takuya [Department of Electronic Science and Engineering, Kyoto University, Kyoto-daigaku Katsura, Nishikyo-ku, Kyoto 615-8510 (Japan)] [Department of Electronic Science and Engineering, Kyoto University, Kyoto-daigaku Katsura, Nishikyo-ku, Kyoto 615-8510 (Japan); Urabe, Keiichiro [Department of Electronic Science and Engineering, Kyoto University, Kyoto-daigaku Katsura, Nishikyo-ku, Kyoto 615-8510 (Japan) [Department of Electronic Science and Engineering, Kyoto University, Kyoto-daigaku Katsura, Nishikyo-ku, Kyoto 615-8510 (Japan); Department of Advanced Materials Science, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8561 (Japan)
2013-07-15T23:59:59.000Z
Numerical predictions and experimental results in this study verify that plasmas with negative permittivity work as functional media for electromagnetic waves and that their composites with metallic metamaterials show further extraordinary properties. Chain structures of individual plasmas with negative permittivity, forming a straight line and a L-shaped bent line, serve flexible waveguides via coupling structures of localized surface waves standing around each plasma. Further progresses as wave controllers are achievable in an array of the composites of plasmas and micro metallic resonators; functions of phase shifters and attenuators are individually controlled, with rotation of working points on the complex refractive index plane by varying gas conditions and permeability modulation. Such proposed sets of flexible combination will lead to advanced scientific products with novel functions.
Komppula, J; Koivisto, H; Laulainen, J; Tarvainen, O
2015-01-01T23:59:59.000Z
Negative ion production with conventional multicusp plasma chambers utilizing 2.45 GHz microwave heating is demonstrated. The experimental results were obtained with the multicusp plasma chambers and extraction systems of the RFdriven RADIS ion source and the filament driven arc discharge ion source LIISA. A waveguide microwave coupling system, which is almost similar to the one used with the SILHI ion source, was used. The results demonstrate that at least one third of negative ion beam obtained with inductive RF-coupling (RADIS) or arc discharge (LIISA) can be achieved with 1 kW of 2.45 GHz microwave power in CW mode without any modification of the plasma chamber. The co-extracted electron to H^- ratio and the optimum pressure range were observed to be similar for both heating methods. The behaviour of the plasma implies that the energy transfer from the microwaves to the plasma electrons is mainly an off-resonance process.
Li, Jiawei; Song, Wei; Huang, Wenhua; Shao, Hao; Huang, Huijun; Shi, Yanchao; Huo, Shaofei; Deng, Yuqun [Northwest Institute of Nuclear Technology, Xi'an 710024 (China)] [Northwest Institute of Nuclear Technology, Xi'an 710024 (China); Zhang, Zhiqiang [Northwest Institute of Nuclear Technology, Xi'an 710024 (China) [Northwest Institute of Nuclear Technology, Xi'an 710024 (China); National Key Laboratory of Antennas and Microwave Technology, Xidian University, Xi'an 710071 (China)
2014-02-15T23:59:59.000Z
The high power microwave (HPM) beam combining results at X-band with an overmoded waveguide diplexer are presented. As the key device for the beam combining experiments, the diplexer is designed, fabricated, and tested. Then the beam combining experiments under short and long pulses are performed at HPM source, respectively. The experiment results reveal that short and long pulse HPM beams have been successfully operated without microwave breakdown at 3-GW with pulse duration of 25?ns and 1.3-GW with pulse duration of 96?ns. According to the experiments, conservative breakdown thresholds for the diplexer are concluded to be 800?kV/cm and 550?kV/cm, respectively, under the short and long pulse HPM conditions.
Si?-implanted Si-wire waveguide photodetectors for the mid-infrared
Souhan, Brian [Columbia Univ., New York, NY (United States); Lu, Ming [Brookhaven National Lab. (BNL), Upton, NY (United States); Grote, Richard R. [Columbia Univ., New York, NY (United States); Chen, Christine P. [Columbia Univ., New York, NY (United States); Huang, Hsu-Cheng [Columbia Univ., New York, NY (United States); Driscoll, Jeffrey B. [Columbia Univ., New York, NY (United States); Stein, Aaron [Brookhaven National Lab. (BNL), Upton, NY (United States); Bakhru, Hassaram [State Univ. of New York at Albany, Albany, NY (United States); Bergman, Keren [Columbia Univ., New York, NY (United States); Green, William M. J. [IBM, Yorktown Heights, NY (United States). Thomas J. Watson Research Center; Osgood, Jr., Richard M. [Columbia Univ., New York, NY (United States)
2014-01-01T23:59:59.000Z
CMOS-compatible Si?-implanted Si-waveguide p-i-n photodetectors operating at room temperature and at mid-infrared wavelengths from 2.2 to 2.3 µm are demonstrated. Responsivities of 9.9 ± 2.0 mA/W are measured at a 5 V reverse bias with an estimated internal quantum efficiency of 2.7 – 4.5%. The dark current is found to vary from a few microamps down to less than a nanoamp after a post-implantation annealing of 350°C. The measured photocurrent dependence on input power shows a linear correspondence over more than three decades, and the frequency response of a 250 µm-length p-i-n device is measured to be ~1.7 GHz for a wavelength of ? = 2.2 µm, thus potentially opening up new communication bands for photonic integrated circuits.
Electromagnetic field of a charge intersecting a cold plasma boundary in a waveguide
Alekhina, Tatiana Yu.; Tyukhtin, Andrey V. [Radiophysics Department of St. Petersburg University, 1 Ulyanovskaya, St. Petersburg 198504 (Russian Federation)
2011-06-15T23:59:59.000Z
We analyze the electromagnetic field of a charge crossing a boundary between a vacuum and cold plasma in a waveguide. We obtain exact expressions for the field components and the spectral density of the transition radiation. With the steepest descent technique, we investigate the field components. We show that the electromagnetic field has a different structure in a vacuum than in cold plasma. We also develop an algorithm for the computation of the field based on a certain transformation of the integration path. The behavior of the field depending on distance and time and the spectral density depending on frequency are explored for different charge velocities. Some important physical effects are noted. A considerable increase and concentration of the field near the wave front in the plasma is observed for the case of ultrarelativistic particles. In the plasma, the mode envelopes and spectral density show zero points when the charge velocity is within certain limits.
Scale-invariant nonlinear optics in gases
Heyl, C M; Miranda, M; Louisy, M; Kovacs, K; Tosa, V; Balogh, E; Varjú, K; L'Huillier, A; Couairon, A; Arnold, C L
2015-01-01T23:59:59.000Z
Nonlinear optical methods are becoming ubiquitous in many areas of modern photonics. They are, however, often limited to a certain range of input parameters, such as pulse energy and average power, since restrictions arise from, for example, parasitic nonlinear effects, damage problems and geometrical considerations. Here, we show that many nonlinear optics phenomena in gaseous media are scale-invariant if spatial coordinates, gas density and laser pulse energy are scaled appropriately. We develop a general scaling model for (3+1)-dimensional wave equations, demonstrating the invariant scaling of nonlinear pulse propagation in gases. Our model is numerically applied to high-order harmonic generation and filamentation as well as experimentally verified using the example of pulse post-compression via filamentation. Our results provide a simple recipe for up-or downscaling of nonlinear processes in gases with numerous applications in many areas of science.
Coherent Vibrational Dynamics and High-Resolution Nonlinear Spectrosco...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Vibrational Dynamics and High-Resolution Nonlinear Spectroscopy: A Comparison with the AirDMSO Liquid Interface. Coherent Vibrational Dynamics and High-Resolution Nonlinear...
MODELING OF STATIC MINING SUBSIDENCE IN A NONLINEAR MEDIUM
Ratigan, J.L.
2013-01-01T23:59:59.000Z
for Static Evaluation of Mining Subsidence," Rep. No. LBL-6, 1981 MODELING OF STATIC MINING SUBSIDENCE IN A NONLINEAR11896 MODELING OF STATIC MINING SUBSIDENCE IN A NONLINEAR ~
Convex Quadratic Relaxations for Mixed-Integer Nonlinear ...
H. Hijazi, C. Coffrin and P. Van Hentenryck
2014-06-03T23:59:59.000Z
nonlinear and mixed-integer nonlinear programs arising in power systems. The ...... International Symposium on Computer Aided Control Systems Design, pp.
Toto the Robot Figure 1. Toto, front view. Figure 2. Toto, rear view.
Indiana University
Toto the Robot Figure 1. Toto, front view. Figure 2. Toto, rear view. Toto the Robot was created so a robot, helps account for his lack of verbal charm. Second, some younger children may recognize in Toto
Farritor, Shane
tap on Shopping Cart, then select term. Tap on Class Search to find courses to place in your shoppingMyRED Mobiles Student Views Mar 2014 Page 1 Login/Sign-in Enter your MyRED /TrueYou credentials. Tap on any Term bar to view a schedule for the selected term. Home Screen/Main Menu Class Schedule
Honors Enrichment Contracts Faculty View Page 1 Honors Enrichment Contracts Faculty View
Honors Enrichment Contracts Faculty View Page 1 Honors Enrichment Contracts Faculty View INITIAL APPROVAL #12;Honors Enrichment Contracts Faculty View Page 2 Summary This document contains information about how to make initial and final decisions on Honors Enrichment Contracts submitted by honors
Groundwater Modeling in ArcView: by integrating ArcView, MODFLOW and
Sengupta, Raja
Groundwater Modeling in ArcView: by integrating ArcView, MODFLOW and MODPATH Abstract Modeling. This paper addresses groundwater modeling which is one of the many entities in environmental modeling in ArcView 3.2a. The objective was to create an integrated system where a user could do groundwater
Barus, R. P. P., E-mail: rismawan.ppb@gmail.com [Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung, Jalan Ganesa 10 Bandung and Centre for Material and Technical Product, Jalan Sangkuriang No. 14 Bandung (Indonesia); Tjokronegoro, H. A.; Leksono, E. [Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung, Jalan Ganesa 10 Bandung (Indonesia); Ismunandar [Chemistry Study, Faculty of Mathematics and Science, Institut Teknologi Bandung, Jalan Ganesa 10 Bandung (Indonesia)
2014-09-25T23:59:59.000Z
Fuel cells are promising new energy conversion devices that are friendly to the environment. A set of control systems are required in order to operate a fuel cell based power plant system optimally. For the purpose of control system design, an accurate fuel cell stack model in describing the dynamics of the real system is needed. Currently, linear model are widely used for fuel cell stack control purposes, but it has limitations in narrow operation range. While nonlinear models lead to nonlinear control implemnetation whos more complex and hard computing. In this research, nonlinear cancellation technique will be used to transform a nonlinear model into a linear form while maintaining the nonlinear characteristics. The transformation is done by replacing the input of the original model by a certain virtual input that has nonlinear relationship with the original input. Then the equality of the two models is tested by running a series of simulation. Input variation of H2, O2 and H2O as well as disturbance input I (current load) are studied by simulation. The error of comparison between the proposed model and the original nonlinear model are less than 1 %. Thus we can conclude that nonlinear cancellation technique can be used to represent fuel cell nonlinear model in a simple linear form while maintaining the nonlinear characteristics and therefore retain the wide operation range.
Fang, Yao-Lung L
2015-01-01T23:59:59.000Z
We study photon correlations generated by scattering from three-level systems (3LS) in one dimension. The two systems studied are a 3LS in a semi-infinite waveguide (3LS plus a mirror) and two 3LS in an infinite waveguide (double 3LS). Our scattering approach naturally connects photon correlation effects with inelastically scattered photons; it corresponds to input-output theory in the weak-probe limit. At the resonance where electromagnetically induced transparency (EIT) occurs, we find that no photons are scattered inelastically and hence there are no induced correlations. Slightly away from EIT, the total inelastically scattered flux is large, being substantially enhanced due to the additional interference paths. This enhancement carries over to the two-photon correlation function, which exhibits non-classical behavior such as strong bunching with a very long time-scale. The long time scale originates from the slow-light effect associated with EIT.
Nonlinear dynamical system approaches towards neural prosthesis
Torikai, Hiroyuki; Hashimoto, Sho [Graduate School of Engineering Science, Osaka University (Japan)
2011-04-19T23:59:59.000Z
An asynchronous discrete-state spiking neurons is a wired system of shift registers that can mimic nonlinear dynamics of an ODE-based neuron model. The control parameter of the neuron is the wiring pattern among the registers and thus they are suitable for on-chip learning. In this paper an asynchronous discrete-state spiking neuron is introduced and its typical nonlinear phenomena are demonstrated. Also, a learning algorithm for a set of neurons is presented and it is demonstrated that the algorithm enables the set of neurons to reconstruct nonlinear dynamics of another set of neurons with unknown parameter values. The learning function is validated by FPGA experiments.
Minimizing radiation damage in nonlinear optical crystals
Cooke, D. Wayne (Santa Fe, NM); Bennett, Bryan L. (Los Alamos, NM); Cockroft, Nigel J. (Santa Fe, NM)
1998-01-01T23:59:59.000Z
Methods are disclosed for minimizing laser induced damage to nonlinear crystals, such as KTP crystals, involving various means for electrically grounding the crystals in order to diffuse electrical discharges within the crystals caused by the incident laser beam. In certain embodiments, electrically conductive material is deposited onto or into surfaces of the nonlinear crystals and the electrically conductive surfaces are connected to an electrical ground. To minimize electrical discharges on crystal surfaces that are not covered by the grounded electrically conductive material, a vacuum may be created around the nonlinear crystal.
Minimizing radiation damage in nonlinear optical crystals
Cooke, D.W.; Bennett, B.L.; Cockroft, N.J.
1998-09-08T23:59:59.000Z
Methods are disclosed for minimizing laser induced damage to nonlinear crystals, such as KTP crystals, involving various means for electrically grounding the crystals in order to diffuse electrical discharges within the crystals caused by the incident laser beam. In certain embodiments, electrically conductive material is deposited onto or into surfaces of the nonlinear crystals and the electrically conductive surfaces are connected to an electrical ground. To minimize electrical discharges on crystal surfaces that are not covered by the grounded electrically conductive material, a vacuum may be created around the nonlinear crystal. 5 figs.
Murphy, Thomas E.
-wavelength pillars on a silicon substrate. Doped silicon can exhibit conductive properties at terahertz frequencies wires [14], parallel plate transmission lines [15], hollow polycarbonate waveguides [16] and corrugated
Sokolov, V I; Marusin, N V; Molchanova, S I; Savelyev, A G; Khaydukov, E V; Panchenko, V Ya [Institute on Laser and Information Technologies, Russian Academy of Sciences, Shatura, Moscow Region (Russian Federation)
2014-11-30T23:59:59.000Z
The problem of reflection of a TE-polarised Gaussian light beam from a layered structure under conditions of resonance excitation of waveguide modes using a total internal reflection prism is considered. Using the spectral approach we have derived the analytic expressions for the mode propagation lengths, widths and depths of m-lines (sharp and narrow dips in the angular dependence of the specular reflection coefficient), depending on the structure parameters. It is shown that in the case of weak coupling, when the propagation lengths l{sub m} of the waveguide modes are mainly determined by the extinction coefficient in the film, the depth of m-lines grows with the mode number m. In the case of strong coupling, when l{sub m} is determined mainly by the radiation of modes into the prism, the depth of m-lines decreases with increasing m. The change in the TE-polarised Gaussian beam shape after its reflection from the layered structure is studied, which is determined by the energy transfer from the incident beam into waveguide modes that propagate along the structure by the distance l{sub m}, are radiated in the direction of specular reflection and interfere with a part of the beam reflected from the working face of the prism. It is shown that this interference can lead to the field intensity oscillations near m-lines. The analysis of different methods for determining the parameters of thin-film structures is presented, including the measurement of mode angles ?{sub m} and the reflected beam shape. The methods are based on simultaneous excitation of a few waveguide modes in the film with a strongly focused monochromatic Gaussian beam, the waist width of which is much smaller than the propagation length of the modes. As an example of using these methods, the refractive index and the thickness of silicon monoxide film on silica substrate at the wavelength 633 nm are determined. (fibre and integrated-optical structures)
Kartashov, I. N., E-mail: igorkartashov@mail.ru; Kuzelev, M. V., E-mail: kuzelev@mail.ru [Moscow State University, Physics Department (Russian Federation)
2014-12-15T23:59:59.000Z
Electromagnetic modes of a plasma waveguide with a nonsimply connected cross section in an external magnetic field are investigated. The existence of quasi-TEM modes in a finite-strength magnetic field is demonstrated. It is shown that, in the limits of infinitely strong and zero magnetic fields, this mode transforms into a true TEM mode. The possibility of excitation of such modes by an electron beam in the regime of the anomalous Doppler effect is analyzed.
Wang, Boyun; Wang, Tao, E-mail: wangtao@hust.edu.cn; Tang, Jian; Li, Xiaoming; Zhu, Youjiang [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China)
2014-10-07T23:59:59.000Z
We theoretically propose a dynamic and ultrafast group delay tuning mechanism in two microcavities side-coupled to a waveguide system through external optical pump beams. The optical Kerr effect modulation method is applied to improve tuning rate with response time of subpicoseconds or even femtoseconds. The group delay of an all-optical analog to electromagnetically induced transparency effect can be controlled by tuning either the frequency of photonic crystal microcavities or the propagation phase of line waveguide. Group delay is controlled between 5.88 and 70.98 ps by dynamically tuning resonant frequencies of the microcavities. Alternatively, the group delay is controlled between 1.86 and 12.08 ps by dynamically tuning the propagation phase of line waveguide. All observed schemes are analyzed rigorously through finite-difference time-domain simulations and coupled-mode formalism. Results show a new direction toward microstructure integration optical pulse trapping and all-optical dynamical storage of light devices in optical communication and quantum information processing.
SEACAS Theory Manuals: Part III. Finite Element Analysis in Nonlinear Solid Mechanics
Laursen, T.A.; Attaway, S.W.; Zadoks, R.I.
1999-03-01T23:59:59.000Z
This report outlines the application of finite element methodology to large deformation solid mechanics problems, detailing also some of the key technological issues that effective finite element formulations must address. The presentation is organized into three major portions: first, a discussion of finite element discretization from the global point of view, emphasizing the relationship between a virtual work principle and the associated fully discrete system, second, a discussion of finite element technology, emphasizing the important theoretical and practical features associated with an individual finite element; and third, detailed description of specific elements that enjoy widespread use, providing some examples of the theoretical ideas already described. Descriptions of problem formulation in nonlinear solid mechanics, nonlinear continuum mechanics, and constitutive modeling are given in three companion reports.
H. Lotfipour; Z. Allameh; R. Roknizadeh; H. Heydari
2015-05-04T23:59:59.000Z
The detection and characterization of a non-classical-squeezed state of light, by using two different schemes, will be presented . In the first one, in an one-dimensional cavity with moving mirror (non-stationary Casimir effect) in the principal mode, we study the photon creation rate for two modes (squeezed and coherent state) of driving field. Since the cavity with moving mirror (similar to an optomechanical system) can be considered analogue to a Kerr-like medium, so that in the second scheme, the probability amplitude for multi-photons absorption in a nonlinear (Kerr) medium will be quantum mechanically calculated. It is shown that because of presence of nonlinear effects, the responses of these two systems to the squeezed versus coherent state are considerably distinguishable. The drastic difference between the results of these two states of light can be viewed as a proposal for detecting of non-classical states.
Parameter Synthesis in Nonlinear Dynamical Systems: Application to Systems Biology
Langmead, Christopher James
Parameter Synthesis in Nonlinear Dynamical Systems: Application to Systems Biology Alexandre Donz. The dynamics of biological processes are often modeled as systems of nonlinear ordinary differential equations problem for nonlinear dynamical systems. That is, for systems of nonlinear ordinary differential equations
Nonlinear Independent Component Analysis: Existence and Uniqueness Results
Hyvärinen, Aapo
\\Lambda Corresponding author 1 #12; Nonlinear Independent Component Analysis: Existence and Uniqueness
Nonlinear transform coding with lossless polar coordinates
Ba, Demba Elimane
2006-01-01T23:59:59.000Z
In conventional transform coding, the importance of preserving desirable quantization partition cell shapes prevents one from considering the use of a nonlinear change of variables. If no linear transformation of a given ...
Nonlinear and Complex Dynamics in Real Systems
Barnett, William A.; Serletis, Apostolos; Serletis, Demitre
2006-06-01T23:59:59.000Z
In this article we provide a review of the literature with respect to fluctuations in real systems and chaos. In doing so, we contrast the order and organization hypothesis of real systems to nonlinear chaotic dynamics and discuss some techniques...
Nonlinear Systems and Complexity Series Editor
Carretero, Ricardo
-Acebedo Editors Localized Excitations in Nonlinear Complex Systems Current State of the Art and Future University California San Diego, USA Jesús Cuevas-Maraver Dept. de Física Aplicada I Escuela Politécnica
Nonlinear multivariate analysis of Neurophysiological Signals
Ernesto Pereda; Rodrigo Quian Quiroga; Joydeep Bhattacharya
2005-10-31T23:59:59.000Z
Multivariate time series analysis is extensively used in neurophysiology with the aim of studying the relationship between simultaneously recorded signals. Recently, advances on information theory and nonlinear dynamical systems theory have allowed the study of various types of synchronization from time series. In this work, we first describe the multivariate linear methods most commonly used in neurophysiology and show that they can be extended to assess the existence of nonlinear interdependences between signals. We then review the concepts of entropy and mutual information followed by a detailed description of nonlinear methods based on the concepts of phase synchronization, generalized synchronization and event synchronization. In all cases, we show how to apply these methods to study different kinds of neurophysiological data. Finally, we illustrate the use of multivariate surrogate data test for the assessment of the strength (strong or weak) and the type (linear or nonlinear) of interdependence between neurophysiological signals.
Rotordynamic instability: nonlinear modeling and analysis
Cooper, Charles Ira
1998-01-01T23:59:59.000Z
A basic rotordynamic model is developed for an crographics. unbalanced rotor connected to a shaft modeled as a continuous beam. This model examines the effects of nonlinear dynamics strictly related to the rotor and shaft. The model dynamics include...
Nonlinear terahertz devices utilizing semiconducting plasmonic metamaterials
Seren, Huseyin R; Keiser, George R; Maddox, Scott J; Zhao, Xiaoguang; Fan, Kebin; Bank, Seth R; Zhang, Xin; Averitt, Richard D
2015-01-01T23:59:59.000Z
The development of responsive metamaterials has enabled the realization of compact tunable photonic devices capable of manipulating the amplitude, polarization, wave vector, and frequency of light. Integration of semiconductors into the active regions of metallic resonators is a proven approach for creating nonlinear metamaterials through optoelectronic control of the semiconductor carrier density. Metal-free subwavelength resonant semiconductor structures offer an alternative approach to create dynamic metamaterials. We present InAs plasmonic disk arrays as a viable resonant metamaterial at terahertz frequencies. Importantly, InAs plasmonic disks exhibit a strong nonlinear response arising from electric field induced intervalley scattering resulting in a reduced carrier mobility thereby damping the plasmonic response. We demonstrate nonlinear perfect absorbers configured as either optical limiters or saturable absorbers, including flexible nonlinear absorbers achieved by transferring the disks to polyimide f...
Perspective Reformulations of Mixed Integer Nonlinear Programs ...
2009-06-02T23:59:59.000Z
Since software for nonlinear programs continues to become more efficient ... Mathematical Sciences Department, IBM T.J. Watson Research Center, P.O. Box 218, York- ...... the instances are reported at http://www.di.unipi.it/optimize/Data/
Nonlinear response theory in chemical kinetics
Kryvohuz, M; Mukamel, S
2014-01-01T23:59:59.000Z
?D(t) are D 0 (t) = (1) Chemical reactions, N h i ( x , t) iOF NONLINEAR RESPONSE THEORY TO CHEMICAL KINETICS Equation (non- linear responses of chemical systems to perturbations
Nonlinear multiferroic phase shifters for microwave frequencies
Ustinov, Alexey B.; Kalinikos, Boris A. [Department of Physical Electronics and Technology, St. Petersburg Electrotechnical University, St. Petersburg 197376 (Russian Federation); Srinivasan, G. [Department of Physics, Oakland University, Rochester, Michigan 48309 (United States)
2014-02-03T23:59:59.000Z
A nonlinear microwave phase shifter based on a planar multiferroic composite has been studied. The multiferroic structure is fabricated in the form of a bilayer consisting of yttrium iron garnet and barium strontium titanate. The principle of operation of the device is based on the linear and nonlinear control of the phase shift of the hybrid spin-electromagnetic waves propagating in the bilayer. The linear control is realized with magnetic and electric fields. The nonlinear control is provided by the input power of microwave signal. The device showed a nonlinear phase shift up to 250°, electric field induced phase shift up to 330°, and magnetic field induced phase shift of more than 180°.
Electromagnetic nonlinear gyrokinetics with polarization drift
Duthoit, F.-X. [SNU Division of Graduate Education for Sustainabilization of Foundation Energy, Seoul National University, Gwanak-ro 1, Gwanak-gu, 151-744 Seoul (Korea, Republic of); Hahm, T. S., E-mail: tshahm@snu.ac.kr [Department of Nuclear Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, 151-744 Seoul (Korea, Republic of); Wang, Lu [College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)
2014-08-15T23:59:59.000Z
A set of new nonlinear electromagnetic gyrokinetic Vlasov equation with polarization drift and gyrokinetic Maxwell equations is systematically derived by using the Lie-transform perturbation method in toroidal geometry. For the first time, we recover the drift-kinetic expression for parallel acceleration [R. M. Kulsrud, in Basic Plasma Physics, edited by A. A. Galeev and R. N. Sudan (North-Holland, Amsterdam, 1983)] from the nonlinear gyrokinetic equations, thereby bridging a gap between the two formulations. This formalism should be useful in addressing nonlinear ion Compton scattering of intermediate-mode-number toroidal Alfvén eigenmodes for which the polarization current nonlinearity [T. S. Hahm and L. Chen, Phys. Rev. Lett. 74, 266 (1995)] and the usual finite Larmor radius effects should compete.
Nonlinear Gravitational Clustering in Expanding Universe
T. Padmanabhan
1996-07-19T23:59:59.000Z
The gravitational clustering of collisionless particles in an expanding universe is modelled using some simple physical ideas. I show that it is possible to understand the nonlinear clustering in terms of three well defined regimes: (1) linear regime; (2) quasilinear regime which is dominated by scale-invariant radial infall and (3) nonlinear regime dominated by nonradial motions and mergers. Modelling each of these regimes separately I show how the nonlinear two point correlation function can be related to the linear correlation function in hierarchical models. This analysis leads to results which are in good agreement with numerical simulations thereby providing an explanation for numerical results. Using this model and some simple extensions, it is possible to understand the transfer of power from large to small scales and the behaviour of higher order correlation functions. The ideas presented here will also serve as a powerful analytical tool to investigate nonlinear clustering in different models.
Fluctuation-induced interactions and nonlinear nanophotonics
Rodriguez-Wong, Alejandro
2010-01-01T23:59:59.000Z
We present theoretical and numerical methods for studying Casimir forces and nonlinear frequency conversion in nanophotonic media consisting of arbitrary geometries and materials. The first section of the thesis focuses ...
QPOs: Einstein's gravity non-linear resonances
Paola Rebusco; Marek A. Abramowicz
2006-01-30T23:59:59.000Z
There is strong evidence that the observed kHz Quasi Periodic Oscillations (QPOs) in the X-ray flux of neutron star and black hole sources in LMXRBs are linked to Einstein's General Relativity. Abramowicz&Klu\\'zniak (2001) suggested a non-linear resonance model to explain the QPOs origin: here we summarize their idea and the development of a mathematical toy-model which begins to throw light on the nature of Einstein's gravity non-linear oscillations.
Nonlinear Quantum Mechanics at the Planck Scale
George Svetlichny
2004-10-27T23:59:59.000Z
I argue that the linearity of quantum mechanics is an emergent feature at the Planck scale, along with the manifold structure of space-time. In this regime the usual causality violation objections to nonlinearity do not apply, and nonlinear effects can be of comparable magnitude to the linear ones and still be highly suppressed at low energies. This can offer alternative approaches to quantum gravity and to the evolution of the early universe.
Interactions and Focusing of Nonlinear Water Waves
Harihar Khanal; Stefan C. Mancas; Shahrdad Sajjadi
2013-02-21T23:59:59.000Z
The coupled cubic nonlinear Schr\\"odinger (CNLS) equations are used to study modulational instabilities of a pair of nonlinearly interacting two-dimensional waves in deep water. It has been shown that the full dynamics of these interacting waves gives rise to localized large-amplitude wavepackets (wave focusing). In this short letter we attempt to verify this result numerically using a Fourier spectral method for the CNLS equations.
MUS420/EE367A Lecture 7B Digital Waveguide Modeling of Bowed Strings
Smith III, Julius Orion
= Friction Curve × Differential Velocity Reaction Force = String Wave Impedance × Velocity Change · Nominally StringBow Bow Velocity (Primary Control) Bow Force Bow Position BridgeString-1 Nut or Finger Lowpass Body into two sections · Bow junction = nonlinear two-port · Primary control variable = bow velocity velocity
Christov, Ivan C.
Introduction Nonlinear Fourier Analysis Ocean Internal Waves KdV Hidden Solitons Closure Two case studies in nonlinear Fourier analysis: Ocean internal solitary waves and the ZabuskyKruskal solitons Ivan Ivan C. Christov (PU) Nonlinear Fourier Analysis INRNE Seminar 1 / 26 #12;Introduction Nonlinear
TotalView Parallel Debugger at NERSC
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Totalview Totalview Description TotalView from Rogue Wave Software is a parallel debugging tool that can be run with up to 512 processors. It provides both X Windows-based...
Incorporating video into Google Mobile Street View
Wright, Christina (Christina E.)
2010-01-01T23:59:59.000Z
Mobile Street View is a compelling application but suffers from significant latency problems, especially in limited bandwidth circumstances. Currently, the application uses static images to display street level information. ...
Cossairt, Oliver S. (Oliver Strider), 1978-
2003-01-01T23:59:59.000Z
This thesis outlines the various techniques for creating electronic 3D displays and analyzes their commercial potential. The thesis argues for the use of view-sequential techniques in the design of 3D displays based on ...
California's Energy Future - The View to 2050
2011-01-01T23:59:59.000Z
carbon capture and storage, especially as a technology thatCarbon capture and sequestration CCST California Council on Science and Technologytechnology California’s Energy Future - The View to 2050 becomes available. ? ? Fossil fuel with carbon capture
Rank Quantization Mountain View, CA, USA
Singh, Jaswinder Pal
Rank Quantization Ravi Kumar Google Mountain View, CA, USA ravi.k53@gmail.com Ronny Lempel Yahoo and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post
California's Energy Future - The View to 2050
2011-01-01T23:59:59.000Z
View to 2050 Laser Fusion Energy a Potential Game Changerworld leader in laser fusion energy—a potential game changera Laser Inertial Fusion Energy (LIFE) power plant would be
Alshehri, Bandar; Dogheche, Elhadj, E-mail: elhadj.dogheche@univ-valenciennes.fr [Institute Electronics, Microelectronics and Nanotechnology (IEMN CNRS), University of Valenciennes, Villeneuve d'Ascq (France); Lee, Seung-Min; Kang, Jin-Ho; Ryu, Sang-Wan, E-mail: sangwan@chonnam.ac.kr [Department of Physics, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Gong, Su-Hyun; Cho, Yong-Hoon [Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701 (Korea, Republic of)
2014-08-04T23:59:59.000Z
In order to modulate the refractive index and the birefringence of Gallium Nitride (GaN), we have developed a chemical etching method to perform porous structures. The aim of this research is to demonstrate that optical properties of GaN can be tuned by controlling the pores density. GaN films are prepared on sapphire by metal organic chemical vapor deposition and the microstructure is characterized by transmission electron microscopy, and scanning electron microscope analysis. Optical waveguide experiment is demonstrated here to determine the key properties as the ordinary (n{sub 0}) and extraordinary (n{sub e}) refractive indices of etched structures. We report here the dispersion of refractive index for porous GaN and compare it to the bulk material. We observe that the refractive index decreases when the porous density p is increased: results obtained at 0.975??m have shown that the ordinary index n{sub 0} is 2.293 for a bulk layer and n{sub 0} is 2.285 for a pores density of 20%. This value corresponds to GaN layer with a pore size of 30?nm and inter-distance of 100?nm. The control of the refractive index into GaN is therefore fundamental for the design of active and passive optical devices.
Nonhydrostatic and nonlinear contributions to the energy flux budget in nonlinear internal waves
Fringer, Oliver B.
Nonhydrostatic and nonlinear contributions to the energy flux budget in nonlinear internal waves S waves. Our results show that the contributions to the total energy flux from these additional terms as well as non- linearity. The partitioning of the incident internal wave energy over the course
Linear Control of Nonlinear Systems The Interplay between Nonlinearity and Feedback
Nikolaou, Michael
1 Linear Control of Nonlinear Systems The Interplay between Nonlinearity and Feedback S. Alper computational methodology that addresses the question of when and what linear control is adequate linear and/or b. the controlled process will be operating closely enough to a steady state for its
Gallium/aluminum nanocomposite material for nonlinear optics and nonlinear plasmonics
Zheludev, Nikolay
Gallium/aluminum nanocomposite material for nonlinear optics and nonlinear plasmonics A. V penetration of gallium into an aluminum film. These composite films form mirrorlike interfaces with silica optics and active plasmonics. The material is a polycrystalline aluminum film on a silica sub- strate
Nonlinear quantum equations: Classical field theory
Rego-Monteiro, M. A.; Nobre, F. D. [Centro Brasileiro de Pesquisas Físicas and National Institute of Science and Technology for Complex Systems, Rua Xavier Sigaud 150, 22290-180 Rio de Janeiro - RJ (Brazil)] [Centro Brasileiro de Pesquisas Físicas and National Institute of Science and Technology for Complex Systems, Rua Xavier Sigaud 150, 22290-180 Rio de Janeiro - RJ (Brazil)
2013-10-15T23:59:59.000Z
An exact classical field theory for nonlinear quantum equations is presented herein. It has been applied recently to a nonlinear Schrödinger equation, and it is shown herein to hold also for a nonlinear generalization of the Klein-Gordon equation. These generalizations were carried by introducing nonlinear terms, characterized by exponents depending on an index q, in such a way that the standard, linear equations, are recovered in the limit q? 1. The main characteristic of this field theory consists on the fact that besides the usual ?(x(vector sign),t), a new field ?(x(vector sign),t) needs to be introduced in the Lagrangian, as well. The field ?(x(vector sign),t), which is defined by means of an additional equation, becomes ?{sup *}(x(vector sign),t) only when q? 1. The solutions for the fields ?(x(vector sign),t) and ?(x(vector sign),t) are found herein, being expressed in terms of a q-plane wave; moreover, both field equations lead to the relation E{sup 2}=p{sup 2}c{sup 2}+m{sup 2}c{sup 4}, for all values of q. The fact that such a classical field theory works well for two very distinct nonlinear quantum equations, namely, the Schrödinger and Klein-Gordon ones, suggests that this procedure should be appropriate for a wider class nonlinear equations. It is shown that the standard global gauge invariance is broken as a consequence of the nonlinearity.
Circuit quantum electrodynamics with a nonlinear resonator
P. Bertet; F. R. Ong; M. Boissonneault; A. Bolduc; F. Mallet; A. C. Doherty; A. Blais; D. Vion; D. Esteve
2011-11-02T23:59:59.000Z
One of the most studied model systems in quantum optics is a two-level atom strongly coupled to a single mode of the electromagnetic field stored in a cavity, a research field named cavity quantum electrodynamics or CQED. CQED has recently received renewed attention due to its implementation with superconducting artificial atoms and coplanar resonators in the so-called circuit quantum electrodynamics (cQED) architecture. In cQED, the couplings can be much stronger than in CQED due to the design flexibility of superconducting circuits and to the enhanced field confinement in one-dimensional cavities. This enabled the realization of fundamental quantum physics and quantum information processing experiments with a degree of control comparable to that obtained in CQED. The purpose of this chapter is to investigate the situation where the resonator to which the atom is coupled is made nonlinear with a Kerr-type nonlinearity, causing its energy levels to be nonequidistant. The system is then described by a nonlinear Jaynes-Cummings Hamiltonian. This considerably enriches the physics since a pumped nonlinear resonator displays bistability, parametric amplification, and squeezing. The interplay of strong coupling and these nonlinear effects constitutes a novel model system for quantum optics that can be implemented experimentally with superconducting circuits. This chapter is organized as follows. In a first section we present the system consisting of a superconducting Kerr nonlinear resonator strongly coupled to a transmon qubit. In the second section, we describe the response of the sole nonlinear resonator to an external drive. In the third section, we show how the resonator bistability can be used to perform a high-fidelity readout of the transmon qubit. In the last section, we investigate the quantum backaction exerted by the intracavity field on the qubit.
Nonlinear wave equation, nonlinear Riemann problem, and the twistor transform of Veronese webs
Ilya Zakharevich
2000-06-04T23:59:59.000Z
Veronese webs are rich geometric structures with deep relationships to various domains of mathematics. The PDEs which determine the Veronese web are overdetermined if dim >3, but in the case dim =3 they reduce to a special flavor of a non-linear wave equation. The symmetries embedded in the definition of a Veronese web reveal themselves as B\\"acklund--Darboux transformations between these non-linear wave equations. On the other hand, the twistor transform identifies Veronese webs with moduli spaces of rational curves on certain complex surfaces. These moduli spaces can be described in terms of the non-linear Riemann problem. This reduces solutions of these non-linear wave equations to the non-linear Riemann problem. We examine these relationships in the particular case of 3-dimensional Veronese webs, simultaneously investigating how these notions relate to general notions of geometry of webs.
Summers, Melissa Erin
2012-01-01T23:59:59.000Z
regions of nonlinear dynamical systems: A constructiveof a class of nonlinear dynamical systems with LMI methodsoutput gain of nonlinear dynamical systems described by
Transmission measurement at 10.6 microns of Te2As3Se5 rib-waveguides on As2S3 substrate
Vigreux-Bercovici, C; Pradel, A; Broquin, J -E; Labadie, L; Kern, P
2007-01-01T23:59:59.000Z
The feasibility of chalcogenide rib waveguides working at lambda = 10.6 microns has been demonstrated. The waveguides comprised a several microns thick Te2As3Se5 film deposited by thermal evaporation on a polished As2S3 glass substrate and further etched by physical etching in Ar or CF4/O2 atmosphere. Output images at 10.6 microns and some propagation losses roughly estimated at 10dB/cm proved that the obtained structures behaved as channel waveguides with a good lateral confinement of the light. The work opens the doors to the realisation of components able to work in the mid and thermal infrared up to 20 microns and even more.
Digital Backpropagation in the Nonlinear Fourier Domain
Wahls, Sander; Prilepsky, Jaroslaw E; Poor, H Vincent; Turitsyn, Sergei K
2015-01-01T23:59:59.000Z
Nonlinear and dispersive transmission impairments in coherent fiber-optic communication systems are often compensated by reverting the nonlinear Schr\\"odinger equation, which describes the evolution of the signal in the link, numerically. This technique is known as digital backpropagation. Typical digital backpropagation algorithms are based on split-step Fourier methods in which the signal has to be discretized in time and space. The need to discretize in both time and space however makes the real-time implementation of digital backpropagation a challenging problem. In this paper, a new fast algorithm for digital backpropagation based on nonlinear Fourier transforms is presented. Aiming at a proof of concept, the main emphasis will be put on fibers with normal dispersion in order to avoid the issue of solitonic components in the signal. However, it is demonstrated that the algorithm also works for anomalous dispersion if the signal power is low enough. Since the spatial evolution of a signal governed by the ...
Nonlinear extraordinary wave in dense plasma
Krasovitskiy, V. B., E-mail: krasovit@mail.ru [Russian Academy of Sciences, Keldysh Institute of Applied Mathematics (Russian Federation); Turikov, V. A. [Russian University of Peoples’ Friendship (Russian Federation)] [Russian University of Peoples’ Friendship (Russian Federation)
2013-10-15T23:59:59.000Z
Conditions for the propagation of a slow extraordinary wave in dense magnetized plasma are found. A solution to the set of relativistic hydrodynamic equations and Maxwell’s equations under the plasma resonance conditions, when the phase velocity of the nonlinear wave is equal to the speed of light, is obtained. The deviation of the wave frequency from the resonance frequency is accompanied by nonlinear longitudinal-transverse oscillations. It is shown that, in this case, the solution to the set of self-consistent equations obtained by averaging the initial equations over the period of high-frequency oscillations has the form of an envelope soliton. The possibility of excitation of a nonlinear wave in plasma by an external electromagnetic pulse is confirmed by numerical simulations.
On Stabilization of Nonautonomous Nonlinear Systems
Bogdanov, A. Yu. [Faculty of Mathematics and IT, Ulyanovsk State University, 42 Leo Tolstoy str., Ulyanovsk, 432970 (Russian Federation)
2008-10-30T23:59:59.000Z
The procedures to obtain the sufficient conditions of asymptotic stability for nonlinear nonstationary continuous-time systems are discussed. We consider different types of the following general controlled system: x = X(t,x,u) = F(t,x)+B(t,x)u, x(t{sub 0}) = x{sub 0}. (*) The basis of investigation is limiting equations, limiting Lyapunov functions, etc. The improved concept of observability of the pair of functional matrices is presented. By these results the problem of synthesis of asymptotically stable control nonlinear nonautonomous systems (with linear parts) involving the quadratic time-dependent Lyapunov functions is solved as well as stabilizing a given unstable system with nonlinear control law.
Nonlinear optical techniques for surface studies. [Monolayers
Shen, Y.R.
1981-09-01T23:59:59.000Z
Recent effort in developing nonlinear optical techniques for surface studies is reviewed. Emphasis is on monolayer detection of adsorbed molecules on surfaces. It is shown that surface coherent antiStokes Raman scattering (CARS) with picosecond pulses has the sensitivity of detecting submonolayer of molecules. On the other hand, second harmonic or sum-frequency generation is also sensitive enough to detect molecular monolayers. Surface-enhanced nonlinear optical effects on some rough metal surfaces have been observed. This facilitates the detection of molecular monolayers on such surfaces, and makes the study of molecular adsorption at a liquid-metal interface feasible. Advantages and disadvantages of the nonlinear optical techniques for surface studies are discussed.
Damage detection in initially nonlinear systems
Bornn, Luke [Los Alamos National Laboratory; Farrar, Charles [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory
2009-01-01T23:59:59.000Z
The primary goal of Structural Health Monitoring (SHM) is to detect structural anomalies before they reach a critical level. Because of the potential life-safety and economic benefits, SHM has been widely studied over the past decade. In recent years there has been an effort to provide solid mathematical and physical underpinnings for these methods; however, most focus on systems that behave linearly in their undamaged state - a condition that often does not hold in complex 'real world' systems and systems for which monitoring begins mid-lifecycle. In this work, we highlight the inadequacy of linear-based methodology in handling initially nonlinear systems. We then show how the recently developed autoregressive support vector machine (AR-SVM) approach to time series modeling can be used for detecting damage in a system that exhibits initially nonlinear response. This process is applied to data acquired from a structure with induced nonlinearity tested in a laboratory environment.
Measurements using tangentially viewing bolometers on TFTR
Bush, C.E.; Schivell, J.; Budny, R.; Ellis R.A. III; Goldston, R.J.; McCune, D.; Medley, S.S.; Scott, S.D.; Towner, H.H.; Wieland, R.M.; and others
1988-08-01T23:59:59.000Z
Co- and counter-viewing bolometers aimed along a common tangency chord are being used to study power losses due to charge exchange (CX) of fast ions in neutral beam injection (NBI) heated TFTR plasmas. For unidirectional injection, tangential bolometers oriented to view CX loss of circulating fast ions detect losses from the thermal target plasma (impurity radiation and CX) plus power due to the fast ion CX loss, whereas bolometers oppositely directed measure only the target plasma contribution. The difference between the two signals is a measure of the fast ion CX loss. Additional information is obtained by comparing the tangential bolometer signals with those of perpendicularly viewing bolometer monitors and arrays. The measurements are compared to results of the TRANSP code analysis.
Fields of View for Environmental Radioactivity
Malins, Alex; Machida, Masahiko; Takemiya, Hiroshi; Saito, Kimiaki
2015-01-01T23:59:59.000Z
The gamma component of air radiation dose rates is a function of the amount and spread of radioactive nuclides in the environment. These radionuclides can be natural or anthropogenic in origin. The field of view describes the area of radionuclides on, or below, the ground that is responsible for determining the air dose rate, and hence correspondingly the external radiation exposure. This work describes Monte Carlo radiation transport calculations for the field of view under a variety of situations. Presented first are results for natural 40K and thorium and uranium series radionuclides distributed homogeneously within the ground. Results are then described for atmospheric radioactive caesium fallout, such as from the Fukushima Daiichi Nuclear Power Plant accident. Various stages of fallout evolution are considered through the depth distribution of 134Cs and 137Cs in soil. The fields of view for the natural radionuclides and radiocaesium are different. This can affect the responses of radiation monitors to th...
View from the Bridge | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousPlasma |Efficiency Â» Searchto IncreaseIntake Event- NTEImprovedMulti-YearView from the Bridge View from the
Derivation of an Applied Nonlinear Schroedinger Equation.
Pitts, Todd Alan; Laine, Mark Richard; Schwarz, Jens; Rambo, Patrick K.; Karelitz, David B.
2015-01-01T23:59:59.000Z
We derive from first principles a mathematical physics model useful for understanding nonlinear optical propagation (including filamentation). All assumptions necessary for the development are clearly explained. We include the Kerr effect, Raman scattering, and ionization (as well as linear and nonlinear shock, diffraction and dispersion). We explain the phenomenological sub-models and each assumption required to arrive at a complete and consistent theoretical description. The development includes the relationship between shock and ionization and demonstrates why inclusion of Drude model impedance effects alters the nature of the shock operator. Unclassified Unlimited Release
Canonical Duality Approach for Nonlinear Dynamical Systems
Ning Ruan; David Y. Gao
2012-06-12T23:59:59.000Z
This paper presents a canonical dual approach for solving a nonlinear population growth problem governed by the well-known logistic equation. Using the finite difference and least squares methods, the nonlinear differential equation is first formulated as a nonconvex optimization problem with unknown parameters. We then prove that by the canonical duality theory, this nonconvex problem is equivalent to a concave maximization problem over a convex feasible space, which can be solved easily to obtain global optimal solution to this challenging problem. Several illustrative examples are presented.
Adaptive Stabilization of Nonlinear Stochastic Systems
Florchinger, P. [URA CNRS No. 399, Departement de Mathematiques, UFR MIM, Universite de Metz, Ile du Saulcy, F 57045 Metz Cedex (France)
1998-07-15T23:59:59.000Z
The purpose of this paper is to study the problem of asymptotic stabilization in probability of nonlinear stochastic differential systems with unknown parameters. With this aim, we introduce the concept of an adaptive control Lyapunov function for stochastic systems and we use the stochastic version of Artstein's theorem to design an adaptive stabilizer. In this framework the problem of adaptive stabilization of a nonlinear stochastic system is reduced to the problem of asymptotic stabilization in probability of a modified system. The design of an adaptive control Lyapunov function is illustrated by the example of adaptively quadratically stabilizable in probability stochastic differential systems.
Nonlinear manipulation and control of matter waves
E. V. Goldstein; M. G. Moore; P. Meystre
1999-06-23T23:59:59.000Z
This paper reviews some of our recent results in nonlinear atom optics. In addition to nonlinear wave-mixing between matter waves, we also discuss the dynamical interplay between optical and matter waves. This new paradigm, which is now within experimental reach, has the potential to impact a number of fields of physics, including the manipulation and applications of atomic coherence, and the preparation of quantum entanglement between microscopic and macroscopic systems. Possible applications include quantum information processing, matter-wave holography, and nanofabrication.
Rahmani, Z., E-mail: z.rahmani@kashanu.ac.ir; Jazi, B. [Department of Laser and Photonics, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Heidari-Semiromi, E. [Department of Condense Matter, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of)
2014-09-15T23:59:59.000Z
The propagation of electromagnetic waves in an elliptical plasma waveguide including strongly magnetized plasma column and a dielectric rod is investigated. The dispersion relation of guided hybrid electromagnetic waves is obtained. Excitation of the waves by a thin annular relativistic elliptical electron beam will be studied. The time growth rate of electromagnetic waves is obtained. The effects of relative permittivity constant of dielectric rod, radius of dielectric rod, accelerating voltage, and current density of the annular elliptical beam on the growth rate and the frequency spectra are numerically presented.
Nonlinear neutrino-photon interactions inside strong laser pulses
Sebastian Meuren; Christoph H. Keitel; Antonino Di Piazza
2015-04-10T23:59:59.000Z
Even though neutrinos are neutral particles and interact only via the exchange of weak gauge bosons, charged leptons and quarks can mediate a coupling to the photon field beyond tree level. Inside a relativistically strong laser field nonlinear effects in the laser amplitude can play an important role, as electrons and positrons interact nonperturbatively with the coherent part of the photon field. Here, we calculate for the first time the leading-order contribution to the axial-vector--vector current-coupling tensor inside an arbitrary plane-wave laser field (which is taken into account exactly by employing the Furry picture). The current-coupling tensor appears in the calculation of various electroweak processes inside strong laser fields like photon emission or trident electron-positron pair production by a neutrino. Moreover, as we will see below, the axial-vector--vector current-coupling tensor contains the Adler-Bell-Jackiw (ABJ) anomaly. This occurrence renders the current-coupling tensor also interesting from a fundamental point of view, as it is the simplest Feynman diagram in an external field featuring this kind of anomaly.
Wang, Kangpeng; Ju, Yongfeng; He, Jin; Zhang, Long, E-mail: jwang@siom.ac.cn, E-mail: lzhang@siom.ac.cn; Wang, Jun, E-mail: jwang@siom.ac.cn, E-mail: lzhang@siom.ac.cn [Key Laboratory of Materials for High-Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Chen, Yu [Key Laboratory for Advanced Materials, Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Blau, Werner J. [Key Laboratory of Materials for High-Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); School of Physics and the Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2 (Ireland)
2014-01-13T23:59:59.000Z
Laser propagation in a tandem structure comprising carbon nanotubes and phthalocyanines is studied by Z-scan method. Due to the different mechanisms of the two materials, the laser beam can be attenuated with different absorptivities, by changing the sequence of light passing through each material. Numerical simulations considering the effect of path length and the change of nonlinear coefficient within each material are conducted for understanding the distribution of laser intensity in the tandem system and hence, fitting of the asymmetric Z-scan curves. The results are helpful for the design of nonlinear optical devices comprising multiple nonlinear materials and mechanisms.
Bosse, J. L.; Huey, B. D. [Department of Materials Science and Engineering, 97 North Eagleville Road, Unit 3136, Storrs, Connecticut 06269-3136 (United States); Tovee, P. D.; Kolosov, O. V., E-mail: o.kolosov@lancaster.ac.uk [Department of Physics, Lancaster University, Lancaster LA1 4YB (United Kingdom)
2014-04-14T23:59:59.000Z
Use of high frequency (HF) vibrations at MHz frequencies in Atomic Force Microscopy (AFM) advanced nanoscale property mapping to video rates, allowed use of cantilever dynamics for mapping nanomechanical properties of stiff materials, sensing ?s time scale phenomena in nanostructures, and enabled detection of subsurface features with nanoscale resolution. All of these methods critically depend on the generally poor characterized HF behaviour of AFM cantilevers in contact with a studied sample, spatial and frequency response of piezotransducers, and transfer of ultrasonic vibrations between the probe and a specimen. Focusing particularly on Ultrasonic Force Microscopy (UFM), this work is also applicable to waveguide UFM, heterodyne force microscopy, and near-field holographic microscopy, all methods that exploit nonlinear tip-surface force interactions at high frequencies. Leveraging automated multidimensional measurements, spectroscopic UFM (sUFM) is introduced to investigate a range of common experimental parameters, including piezotransducer excitation frequency, probed position, ultrasonic amplitude, cantilever geometry, spring constant, and normal force. Consistent with studies of influence of each of these factors, the data-rich sUFM signatures allow efficient optimization of ultrasonic-AFM based measurements, leading to best practices recommendations of using longer cantilevers with lower fundamental resonance, while at the same time increasing the central frequency of HF piezo-actuators, and only comparing results within areas on the order of few ?m{sup 2} unless calibrated directly or compared with in-the-imaged area standards. Diverse materials such as Si, Cr, and photoresist are specifically investigated. This work thereby provides essential insight into the reliable use of MHz vibrations with AFM and provides direct evidence substantiating phenomena such as sensitivity to adhesion, diminished friction for certain ultrasonic conditions, and the particular benefit of UFM and related methods for nanoscale mapping of stiff materials.
BLUE VIEW VISION INSIGHT! Good news--your vision plan
California at Santa Cruz, University of
WELCOME TO BLUE VIEW VISION INSIGHT! Good news--your vision plan is flexible and easy to use, your discounts, and much more! Blue View Vision InsightSM University of California Student Health Insurance Plan (UC SHIP) 2013/14 Your Blue View Vision Insight Network Blue View Vision Insight offers you
BLUE VIEW VISION INSIGHT! Good news--your vision plan
Barrett, Jeffrey A.
WELCOME TO BLUE VIEW VISION INSIGHT! Good news--your vision plan is flexible and easy to use, your discounts, and much more! Blue View Vision InsightSM University of California Student Health Insurance Plan (UC SHIP) 2012/13 Your Blue View Vision Insight Network Blue View Vision Insight offers you
BLUE VIEW VISION INSIGHT! Good news--your vision plan
Mease, Kenneth D.
WELCOME TO BLUE VIEW VISION INSIGHT! Good news--your vision plan is flexible and easy to use, your discounts, and much more! Blue View VisionSM Insight University of California Student Health Insurance Plan (UC SHIP) 2014/15 Your Blue View Vision Insight network Blue View Vision Insight offers you
Stability analysis for class of switched nonlinear systems
Shaker, Hamid Reza
Stability analysis for a class of switched nonlinear systems is addressed in this paper. Two linear matrix inequality (LMI) based sufficient conditions for asymptotic stability are proposed for switched nonlinear systems. ...
Nonlinear adaptive internal model control using neural networks
Gandhi, Amit Krushnavadan
2001-01-01T23:59:59.000Z
(NIMC) strategy based on neural network models is presented for SISO processes. The nonlinearities of the dynamical system are modelled by neural network architectures. Recurrent neural networks can be used for both the identification and control of nonlinear...
Nonlinear Pricing Strategies and Market Concentration in the Airline Industry
Hernandez Garcia, Manuel A.
2010-10-12T23:59:59.000Z
This dissertation investigates the effect of market concentration on nonlinear pricing strategies in the airline industry. The study develops a theoretical nonlinear pricing model with both discrete product and consumer ...
Nonlinear springs with applications to flow regulation valves and mechanisms
Freeman, David Calvin
2008-01-01T23:59:59.000Z
This thesis focuses on the application of nonlinear springs for fluid flow control valves where geometric constraints, or fabrication technologies, limit the use of available solutions. Types of existing nonlinear springs ...
Orbital stability of periodic waves for the nonlinear Schrodinger equation
Gallay, Thierry
Orbital stability of periodic waves for the nonlinear SchrË?odinger equation Thierry Gallay Institut: Thierry Gallay, Thierry.Gallay@ujfÂgrenoble.fr Keywords: Nonlinear SchrË?odinger equation, periodic waves
Orbital stability of periodic waves for the nonlinear Schrodinger equation
Orbital stability of periodic waves for the nonlinear SchrÂ¨odinger equation Thierry Gallay Institut: Thierry Gallay, Thierry.Gallay@ujf-grenoble.fr Keywords: Nonlinear SchrÂ¨odinger equation, periodic waves
Orbital stability of periodic waves for the nonlinear Schrodinger equation
Boyer, Edmond
Orbital stability of periodic waves for the nonlinear Schr¨odinger equation Thierry Gallay Institut: Thierry Gallay, Thierry.Gallay@ujf-grenoble.fr Keywords: Nonlinear Schr¨odinger equation, periodic waves
Nonlinear stochastic system identification techniques for biological tissues/
Chen, Yi, S.M. Massachusetts Institute of Technology
2010-01-01T23:59:59.000Z
This research develops a device capable of measuring the nonlinear dynamic mechanical properties of human tissue in vivo. The enabling technology is the use of nonlinear stochastic system identification techniques in ...
INVESTIGATION Retrospective View of North American Potato
Douches, David S.
INVESTIGATION Retrospective View of North American Potato (Solanum tuberosum L.) Breeding in the 20, Madison, Wisconsin, 53706 ABSTRACT Cultivated potato (Solanum tuberosum L.), a vegetatively propagated explore the effects of potato breeding at the genome level, we used 8303 single-nucleotide polymorphism
A VIEW OF MATHEMATICS Alain CONNES
Connes, Alain
A VIEW OF MATHEMATICS Alain CONNES Mathematics is the backbone of modern science and a remarkably e#cient source of new concepts and tools to understand the ``reality'' in which we participate. It plays a basic role in the great new theories of physics of the XXth century such as general relativity, and quantum
A VIEW OF MATHEMATICS Alain CONNES
Connes, Alain
A VIEW OF MATHEMATICS Alain CONNES Mathematics is the backbone of modern science and a remarkably efficient source of new concepts and tools to understand the "reality" in which we participate. It plays a basic role in the great new theories of physics of the XXth century such as general relativity
Corroborating Information from Disagreeing Views Alban Galland
Doyen, Laurent
variety of information and viewpoints from individual Web sources that have different degree sources, many sources will continue to list outdated information if a person has switched jobsCorroborating Information from Disagreeing Views Alban Galland INRIA Saclay Île-de-France LSV ENS
Longer View The Road Less Driven
Handy, Susan L.
Longer View The Road Less Driven Susan Handy I n September 2005, Hurricane Katrina slammed into New.S. Department of Energy [DOE], 2005a), a level unseen in inflation-adjusted terms even at the peak of the late 1970s energy crisis (DOE, 2005b). Shortages in the gasoline supply occurred temporarily in many parts
Two (Related) World Views Edward N. Zalta
Zalta, Edward N.
, and applied that theory to the analysis of thought, language, and the structure of the world. Casta by Plantinga in [1983]. Plantinga puts his finger squarely on some fundamental intuitions that guise theoryTwo (Related) World Views Edward N. Zalta Center for the Study of Language and Information Stanford
Friction in full view A. P. Merklea
Marks, Laurence D.
Friction in full view A. P. Merklea and L. D. Marksb Materials Science and Engineering proposed friction mechanisms explaining the unique tribological properties of graphite. Wear of graphite chemical or struc- tural information from the interface during a friction experi- ment. Examples
CITY OF MOUNTAIN VIEW April 12, 2011 .
Ordinance ordinance? Projected effective date: September 1, 2011 Green building or stand-alone energy Energy Ordinance in Combination with Green Building ordinance? Do minimum energy requirements increase No afterCITY OF MOUNTAIN VIEW April 12, 2011 . CaUfomia Energy Commission Attn: Joe Loyer 1516 Ninth
Allen, Matthew S.
Identifying parameters of nonlinear structural dynamic systems using linear time- periodic nonlinearity. 1. Introduction Most dynamical systems behave nonlinearly in the most general scenario. This can point bifurcation [1], in rotor dynamic systems with bearing contact nonlinearities [2], in biomechanics
Background Simulation Experiment Conclusion Hysteresis in the Nonlinear Tunnelling of Light
Petta, Jason
Background Simulation Experiment Conclusion Hysteresis in the Nonlinear Tunnelling of Light Through of Light Through a Barrier #12;Background Simulation Experiment Conclusion Outline 1 Background Nonlinear of Light Through a Barrier #12;Background Simulation Experiment Conclusion Nonlinear Optics Nonlinear
Nonlinear Integral Equations for the Inverse Problem in Corrosion ...
2012-06-15T23:59:59.000Z
Nonlinear Integral Equations for the Inverse. Problem in Corrosion Detection from Partial. Cauchy Data. Fioralba Cakoni. Department of Mathematical Sciences, ...
Nonlinear Analysis of a Two DOF Piecewise Linear Aeroelastic System
Elgohary, Tarek Adel Abdelsalam
2011-10-21T23:59:59.000Z
model were introduced with special emphasis on numerical simulations. Dowell et al. (2003) also introduced a good review for the problem discussing nonlinear aeroelasticity and its effects on flight and its association with limit cycle oscillations... as a result of those nonlinearities. Aerodynamics nonlinearities were tackled separately by Ueda and Dowell (1984). A typical airfoil section with transonic aerodynamic nonlinearities was analyzed. The describing function method was used...
The Fourth International Conference NONLINEAR DYNAMICS
Paris-Sud XI, Université de
The Fourth International Conference NONLINEAR DYNAMICS June, 19-22, 2013 PROCEEDINGS #12;Ministry of Mechanics NAS of Ukraine (Kiev, UKRAINE) McGill University (Montreal, CANADA) The Fourth International-617-669-100-6 4- The book of Proceedings includes extended abstracts of presentations on the Fourth International
Anomalous optical nonlinearity of dielectric nanodispersions
Milichko, V A; Dzyuba, V P; Kul'chin, Yurii N
2013-06-30T23:59:59.000Z
We present the results of studying the nonlinear optical response of nanodispersions of semiconductor (TiO{sub 2}, ZnO) and dielectric (SiO{sub 2}, Al{sub 2}O{sub 3}) nanoparticles of spherical, spheroidal and flake shape, suspended in polar and nonpolar dielectric matrices (water, isopropanol, polymethylsiloxane and transformer oil) by means of z-scanning in the field of low-intensity visible laser radiation. It is found that, unlike semiconductor nanoparticles and particles of spherical shape, flake-shaped SiO{sub 2} and Al{sub 2}O{sub 3} nanoparticles suspended in nonpolar matrices exhibit nonlinear optical response within the intensity interval from 0 to 500 W cm{sup -2} that vanishes at higher intensities. The diagrams of energy states of the optical electrons in nanoparticles that allow explanation of differences in the nonlinear-optical properties of nanodispersions are proposed. Good agreement between the experimental and theoretical dependences of nonlinear refractive indices and absorption coefficients on the intensity of radiation is observed. (optical nanostructures)
Nonlinear Contraction Tools for Constrained Optimization
Jonathan Soto; Jean-Jacques E. Slotine
2012-06-07T23:59:59.000Z
This paper describes new results linking constrained optimization theory and nonlinear contraction analysis. Generalizations of Lagrange parameters are derived based on projecting system dynamics on the tangent space of possibly time-varying constraints. The paper formalizes the intuition that, just as convexity rather than linearity is the key property in optimization, contraction rather than linearity is the key dynamical property in this context.
Random Walks and Nonlinear Dynamics in the
Frey, Erwin
in the experimental biophysics and state-of-the-art concepts of modern nonlinear dynamics and random-walk theory leading experts in cell biology and theoretical physics in order to tie recent advances: Visitors Program Mandy Lochar MPI for the Physics of Complex Systems Nöthnitzer Str. 38, D-01187 Dresden