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

Abstract

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 variational 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.

Authors:
 [1];  [1];  [2];  [3];  [3];  [3];  [3];  [3];  [3];  [4];  [4]
  1. Univ. of Rzeszow, Pigonia (Poland)
  2. Center for Microelectronics and Nanotechnology, University of Rzeszow
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  4. Polish Academy of Sciences (PAS), Warsaw (Poland)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1345961
Report Number(s):
LA-UR-17-21891
DOE Contract Number:
AC52-06NA25396
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; High Magnetic Field Science

Citation Formats

Zybert, M., Marchweka, M., Sheregii, E. M., Rickel, Dwight Gene, Betts, Jonathan Bobby, Balakirev, Fedor Fedorovich, Gordon, Michael Joseph, Stier, Andreas V., Mielke, Charles H., Pfeffer, P., and Zawadski, W. Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at mega-gauss magnetic fields. United States: N. p., 2017. Web. doi:10.2172/1345961.
Zybert, M., Marchweka, M., Sheregii, E. M., Rickel, Dwight Gene, Betts, Jonathan Bobby, Balakirev, Fedor Fedorovich, Gordon, Michael Joseph, Stier, Andreas V., Mielke, Charles H., Pfeffer, P., & Zawadski, W. Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at mega-gauss magnetic fields. United States. doi:10.2172/1345961.
Zybert, M., Marchweka, M., Sheregii, E. M., Rickel, Dwight Gene, Betts, Jonathan Bobby, Balakirev, Fedor Fedorovich, Gordon, Michael Joseph, Stier, Andreas V., Mielke, Charles H., Pfeffer, P., and Zawadski, W. Mon . "Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at mega-gauss magnetic fields". United States. doi:10.2172/1345961. https://www.osti.gov/servlets/purl/1345961.
@article{osti_1345961,
title = {Landau levels and shallow donor states in GaAs/AlGaAs multiple quantum wells at mega-gauss magnetic fields},
author = {Zybert, M. and Marchweka, M. and Sheregii, E. M. and Rickel, Dwight Gene and Betts, Jonathan Bobby and Balakirev, Fedor Fedorovich and Gordon, Michael Joseph and Stier, Andreas V. and Mielke, Charles H. and Pfeffer, P. and Zawadski, W.},
abstractNote = {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 variational 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.},
doi = {10.2172/1345961},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Mar 06 00:00:00 EST 2017},
month = {Mon Mar 06 00:00:00 EST 2017}
}

Technical Report:

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