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Modulation of Noise in Submicron GaAs/AlGaAs Hall Devices by Gating

Yongqing Li·Cong Ren·Peng Xiong·Stephan von Molnar·Yuzo Ohno·Hideo Ohno
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Abstract

We present a systematic characterization of fluctuations in submicron Hall devices based on GaAs/AlGaAs two-dimensional electron gas heterostructures at temperatures between 1.5 K to 60 K. A large variety of noise spectra, from 1/f to Lorentzian, are obtained by gating the Hall devices. The noise level can be reduced by up to several orders of magnitude with a moderate gate voltage of 0.2 V, whereas the carrier density increases less than 60% in the same range. The significant dependence of the Hall noise spectra on temperature and gate voltage is explained in terms of the switching processes related to impurities in n-AlGaAs.

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Yongqing Li, Cong Ren, Peng Xiong, Stephan von Molnar, Yuzo Ohno, Hideo Ohno. 2004-06-21. Modulation of Noise in Submicron GaAs/AlGaAs Hall Devices by Gating. https://doi.org/10.1103/physrevlett.93.246602

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