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Title: Nonequilibrium chemical potential in a two-dimensional electron gas in the quantum-Hall-effect regime

Abstract

The nonequilibrium state of a two-dimensional electron gas in the quantum-Hall-effect regime is studied in Hall bars equipped with additional inner contacts situated within the bar. The magnetic-field dependence of the voltage drop between different contact pairs are studied at various temperatures. It was found that the voltage between the inner and outer contacts exhibits peaks of significant amplitude in narrow magnetic-field intervals near integer filling factors. Furthermore, the magnetic-field dependence of the voltage in these intervals exhibits a hysteresis, whereas the voltage between the outer contacts remains zero in the entire magnetic-field range. The appearance of the observed voltage peaks and their hysteretic behavior can be explained by an imbalance between the chemical potentials of edge and bulk states, resulting from nonequilibrium charge redistribution between the edge and bulk states when the magnetic field sweeps under conditions of the quantum Hall effect. The results of the study significantly complement the conventional picture of the quantum Hall effect, explicitly indicating the existence of a significant imbalance at the edge of the two-dimensional electron gas: the experimentally observed difference between the electrochemical potentials of the edge and bulk exceeds the distance between Landau levels by tens of times.

Authors:
; ; ; ;  [1]
  1. Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation)
Publication Date:
OSTI Identifier:
22649725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 50; Journal Issue: 8; Other Information: Copyright (c) 2016 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ELECTRIC POTENTIAL; ELECTROCHEMISTRY; ELECTRON GAS; ENERGY LEVELS; HALL EFFECT; HYSTERESIS; MAGNETIC FIELDS; POTENTIALS; TWO-DIMENSIONAL SYSTEMS; VOLTAGE DROP

Citation Formats

Pokhabov, D. A., E-mail: pokhabov@isp.nsc.ru, Pogosov, A. G., Budantsev, M. V., Zhdanov, E. Yu., and Bakarov, A. K. Nonequilibrium chemical potential in a two-dimensional electron gas in the quantum-Hall-effect regime. United States: N. p., 2016. Web. doi:10.1134/S1063782616080170.
Pokhabov, D. A., E-mail: pokhabov@isp.nsc.ru, Pogosov, A. G., Budantsev, M. V., Zhdanov, E. Yu., & Bakarov, A. K. Nonequilibrium chemical potential in a two-dimensional electron gas in the quantum-Hall-effect regime. United States. doi:10.1134/S1063782616080170.
Pokhabov, D. A., E-mail: pokhabov@isp.nsc.ru, Pogosov, A. G., Budantsev, M. V., Zhdanov, E. Yu., and Bakarov, A. K. Mon . "Nonequilibrium chemical potential in a two-dimensional electron gas in the quantum-Hall-effect regime". United States. doi:10.1134/S1063782616080170.
@article{osti_22649725,
title = {Nonequilibrium chemical potential in a two-dimensional electron gas in the quantum-Hall-effect regime},
author = {Pokhabov, D. A., E-mail: pokhabov@isp.nsc.ru and Pogosov, A. G. and Budantsev, M. V. and Zhdanov, E. Yu. and Bakarov, A. K.},
abstractNote = {The nonequilibrium state of a two-dimensional electron gas in the quantum-Hall-effect regime is studied in Hall bars equipped with additional inner contacts situated within the bar. The magnetic-field dependence of the voltage drop between different contact pairs are studied at various temperatures. It was found that the voltage between the inner and outer contacts exhibits peaks of significant amplitude in narrow magnetic-field intervals near integer filling factors. Furthermore, the magnetic-field dependence of the voltage in these intervals exhibits a hysteresis, whereas the voltage between the outer contacts remains zero in the entire magnetic-field range. The appearance of the observed voltage peaks and their hysteretic behavior can be explained by an imbalance between the chemical potentials of edge and bulk states, resulting from nonequilibrium charge redistribution between the edge and bulk states when the magnetic field sweeps under conditions of the quantum Hall effect. The results of the study significantly complement the conventional picture of the quantum Hall effect, explicitly indicating the existence of a significant imbalance at the edge of the two-dimensional electron gas: the experimentally observed difference between the electrochemical potentials of the edge and bulk exceeds the distance between Landau levels by tens of times.},
doi = {10.1134/S1063782616080170},
journal = {Semiconductors},
number = 8,
volume = 50,
place = {United States},
year = {Mon Aug 15 00:00:00 EDT 2016},
month = {Mon Aug 15 00:00:00 EDT 2016}
}