Charge metastability and hysteresis in the quantum Hall regime

Article

关键词: 2-DIMENSIONAL ELECTRON-SYSTEM;    SURFACE ACOUSTIC-WAVES;    LANDAU-LEVEL;    TRANSITIONS;    GAS;    FERROMAGNETISM;    PROPAGATION;    SPIKES;    MODEL;   

DOI  :  10.1103/PhysRevB.94.245440

来源: SCIE

【 摘 要 】

We report simultaneous quasi-dc magnetotransport and high-frequency surface acoustic wave measurements on bilayer two-dimensional electron systems in GaAs. Near strong integer quantized Hall states, a strong magnetic-field-sweep hysteresis in the velocity of the acoustic waves is observed at low temperatures. This hysteresis indicates the presence of a metastable state with anomalously high conductivity in the interior of the sample. This nonequilibrium state is not revealed by conventional low-frequency transport measurements which are dominated by dissipationless transport at the edge of the two-dimensional system. We find that a field-cooling technique allows the equilibrium charge configuration within the interior of the sample to be established. A simple model for this behavior is discussed.

【 授权许可】

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