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Title: Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at megagauss magnetic fields

Authors:
; ; ; ; ; ; ; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1348864
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 95; Journal Issue: 11; Related Information: CHORUS Timestamp: 2017-03-27 22:09:18; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Zybert, M., Marchewka, M., Sheregii, E. M., Rickel, D. G., Betts, J. B., Balakirev, F. F., Gordon, M., Stier, A. V., Mielke, C. H., Pfeffer, P., and Zawadzki, W.. Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at megagauss magnetic fields. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.95.115432.
Zybert, M., Marchewka, M., Sheregii, E. M., Rickel, D. G., Betts, J. B., Balakirev, F. F., Gordon, M., Stier, A. V., Mielke, C. H., Pfeffer, P., & Zawadzki, W.. Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at megagauss magnetic fields. United States. doi:10.1103/PhysRevB.95.115432.
Zybert, M., Marchewka, M., Sheregii, E. M., Rickel, D. G., Betts, J. B., Balakirev, F. F., Gordon, M., Stier, A. V., Mielke, C. H., Pfeffer, P., and Zawadzki, W.. Mon . "Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at megagauss magnetic fields". United States. doi:10.1103/PhysRevB.95.115432.
@article{osti_1348864,
title = {Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at megagauss magnetic fields},
author = {Zybert, M. and Marchewka, M. and Sheregii, E. M. and Rickel, D. G. and Betts, J. B. and Balakirev, F. F. and Gordon, M. and Stier, A. V. and Mielke, C. H. and Pfeffer, P. and Zawadzki, W.},
abstractNote = {},
doi = {10.1103/PhysRevB.95.115432},
journal = {Physical Review B},
number = 11,
volume = 95,
place = {United States},
year = {Mon Mar 27 00:00:00 EDT 2017},
month = {Mon Mar 27 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevB.95.115432

Citation Metrics:
Cited by: 1work
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  • Landau levels and shallow donor states in multiple GaAs/AlGaAs quantum wells (MQWs) are investigated by means of the cyclotron resonance at mega-gauss magnetic fields. Measurements of magneto-optical transitions were performed in pulsed fields up to 140 T and temperatures from 6 to 300 K. The 14 x 14 P.p band model for GaAs is used to interpret free-electron transitions in a magnetic field. Temperature behavior of the observed resonant structure indicates, in addition to the free-electron Landau states, contributions of magneto-donor states in the GaAs wells and possibly in the AlGaAs barriers. The magneto-donor energies are calculated using a variationalmore » procedure suitable for high magnetic fields and accounting for conduction band nonparabolicity in GaAs. It is shown that the above states, including their spin splitting, allow one to interpret the observed mengeto-optical transitions in MQWs in the middle infrared region. Our experimental and theoretical results at very high magnetic fields are consistent with the picture used previously for GaAs/AlGaAs MQWs at lower magnetic fields.« less
  • The characteristics of the Coulomb scattering of conduction electrons at shallow donor centers in Al{sub x}Ga{sub 1-x}As/n-GaAs/Al{sub x}Ga{sub 1-x}As quantum well heterostructures are studied theoretically with consideration for the influence of resonance states. The resonance states emerge below the excited quantum-confinement subbands because of the presence of donors. It is found that the spectra of total and transport Coulomb-scattering cross sections exhibit asymmetric resonance features in the vicinity of resonance energies. It is shown that these features do not exhibit a small effect: in the vicinity of resonance energies, the cross sections can differ from the corresponding quantities in themore » nonresonance case several times.« less
  • Photoconductors utilizing planar-doped silicon shallow donors in GaAs quantum wells formed with AlGaAs barriers have been fabricated and measured to have far-infrared (FIR) resonant-wavelength responsivities of {approximately}1 V W{sup {minus}1}, with noise equivalent power values of {approximately}1 X 10{sup {minus}7} W Hz{sup {minus}1/2} at 4 K. The technology makes possible the use of FIR photoconductive magnetospectroscopy to measure the well position of sheet-doped silicon ions when incorporated at doping levels below 1X10{sup 16} cm{sup {minus}3}. A comparison of the measured position of the ions with the intended position reveals a discrepancy that can be linked to the growth parameters usedmore » to produce the structure. 10 refs., 5 figs.« less
  • We report operation of a new surface-emitting laser. This epitaxial laser is fabricated with molecular beam epitaxy by the growth of quarter-wave high reflectors of AlAs/Al/sub 0.4/Ga/sub 0.6/As (710 A/630 A) which surround a 4.5-..mu..m-thick multiple quantum well of GaAs/Al/sub 0.4/Ga/sub 0.6/As (100 A/200 A). We characterize the structure with cw spectroscopy (absorption, reflection, and luminescence) and investigate stimulated emission spectra under pulsed photopumping. When photopumped, the structure lases in its as-grown condition without need of substrate removal, cleaving, or heatsinking. The lasing wavelength is as short as 7400 A and can be tuned to as long as 8400 Amore » by positioning the pump spot to different regions across the wafer. The pulsed threshold irradiance has a very weak temperature dependence varying from 6 x 10/sup 5/ W/cm/sup 2/ at 4.2 K to 1.6 x 10/sup 6/ W/cm/sup 2/ at 295 K.« less
  • {sup 71}Ga NMR spectroscopy was performed on GaAs/AlGaAs quantum wells to measure the electron spin polarization for Landau filling factors 0.7{le}{nu}{le}3.5 . A reduction of the spin polarization was observed when {nu} deviated from 3, suggesting that the effective spin of the charged excitations in the quantum wells was larger than that of a single electron. This finding may be evidence of Skyrmion excitations for {nu}=3 . {copyright} {ital 1999} {ital The American Physical Society}