Modulation of noise in submicron GaAs/AlGaAs hall devices by gating.
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 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.
Li
Yongqing
Y
MARTECH and Department of Physics, Florida State University, Tallahassee, FL 32306-4351, USA.
Ren
Cong
C
Xiong
Peng
P
von Molnár
Stephan
S
Ohno
Yuzo
Y
Ohno
Hideo
H