Magnetization measurements of high-mobility two-dimensional electron gases
Magnetization measurements of high-mobility two-dimensional electron gases
De Haas-van Alphen (dHvA) oscillations are observed for Landau levels (LLs) with filling factors between 4 and 52, at temperatures in the range 50 mK to 1 K, in experiments on high mobility GaAs/(Al, Ga)As heterojunctions. The oscillations become sawtooth-shaped at low filling factors, and theoretical fits to the data, assuming the two-dimensional electron gas to be a non-interacting Fermi system, show the shape of LLs to be close to a ?-function. The small residual width (~0.4 meV or less) fits equally well to either a Gausian or a Lorentzian density of states model. In almost all cases, a constant background density of states has to be included to obtain a satisfactory fit. weak odd-filling-factor dHvA peaks are detected at high fields, from which a g-factor enhancement of 15 can be inferred. Comparison of the scattering time derived from the fits before and after illumination, with the momentum relaxation time derived from transport, reveals a counterintuitive behavior in the bulk-modulation-doped sample.
155329
Zhu, M.
3f4cc18c-a721-4422-93c0-5cf03bd1f9da
Usher, A.
c35eff09-3353-4b8c-a735-8272a3ced1f8
Matthews, A. J.
181809e8-3bc1-4004-9c24-ff6e32b7c984
Potts, A.
60d57f4c-abcf-4b6b-8247-28711e6fd4d4
Elliott, M.
72144b37-250f-4bf8-8454-0c17e1318bfa
Herrenden-Harker, W. G.
e9030a74-e078-4d68-8efc-99d753fd65e8
Ritchie, D. A.
efa64786-3cb8-47f4-98d5-e8cce27bb1e7
Simmons, M. Y.
6a05d50b-57f0-4d71-a4ae-5a38cede98f0
April 2003
Zhu, M.
3f4cc18c-a721-4422-93c0-5cf03bd1f9da
Usher, A.
c35eff09-3353-4b8c-a735-8272a3ced1f8
Matthews, A. J.
181809e8-3bc1-4004-9c24-ff6e32b7c984
Potts, A.
60d57f4c-abcf-4b6b-8247-28711e6fd4d4
Elliott, M.
72144b37-250f-4bf8-8454-0c17e1318bfa
Herrenden-Harker, W. G.
e9030a74-e078-4d68-8efc-99d753fd65e8
Ritchie, D. A.
efa64786-3cb8-47f4-98d5-e8cce27bb1e7
Simmons, M. Y.
6a05d50b-57f0-4d71-a4ae-5a38cede98f0
Zhu, M., Usher, A., Matthews, A. J., Potts, A., Elliott, M., Herrenden-Harker, W. G., Ritchie, D. A. and Simmons, M. Y.
(2003)
Magnetization measurements of high-mobility two-dimensional electron gases.
Physical Review B, 67, .
Abstract
De Haas-van Alphen (dHvA) oscillations are observed for Landau levels (LLs) with filling factors between 4 and 52, at temperatures in the range 50 mK to 1 K, in experiments on high mobility GaAs/(Al, Ga)As heterojunctions. The oscillations become sawtooth-shaped at low filling factors, and theoretical fits to the data, assuming the two-dimensional electron gas to be a non-interacting Fermi system, show the shape of LLs to be close to a ?-function. The small residual width (~0.4 meV or less) fits equally well to either a Gausian or a Lorentzian density of states model. In almost all cases, a constant background density of states has to be included to obtain a satisfactory fit. weak odd-filling-factor dHvA peaks are detected at high fields, from which a g-factor enhancement of 15 can be inferred. Comparison of the scattering time derived from the fits before and after illumination, with the momentum relaxation time derived from transport, reveals a counterintuitive behavior in the bulk-modulation-doped sample.
More information
Published date: April 2003
Organisations:
Nanoelectronics and Nanotechnology
Identifiers
Local EPrints ID: 262117
URI: http://eprints.soton.ac.uk/id/eprint/262117
ISSN: 1550-235X
PURE UUID: 2d79b321-062b-41b2-9dec-8eec8774744b
Catalogue record
Date deposited: 23 Mar 2006
Last modified: 14 Mar 2024 07:05
Export record
Contributors
Author:
M. Zhu
Author:
A. Usher
Author:
A. J. Matthews
Author:
A. Potts
Author:
M. Elliott
Author:
W. G. Herrenden-Harker
Author:
D. A. Ritchie
Author:
M. Y. Simmons
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics