Universal conductance fluctuations and electron coherence lengths in a narrow two-dimensional electron gas

Recent studies of transport through ballistic quantum dot resonators have revealed a complex array of behavior, including the existence of "universal" conductance fluctuations which are presumed to arise from the chaotic behavior of the underlying classical dynamics. In this paper, the results of studies on the classical ballistic transport of carriers, within a quasi-two-dimensional electron gas, through a 1.0 micron square structure in a magnetic field are presented.

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Mesoscopic conductance fluctuations of a two-dimensional electron gas in a one-dimensional lattice of antidots

Superlattices and Microstructures ◽

10.1006/spmi.1996.0240 ◽

1998 ◽

Vol 24 (4) ◽

pp. 291-293 ◽

Cited By ~ 2

Author(s):

M.V. Budantsev ◽

Z.D. Kvon ◽

A.G. Pogosov ◽

L.V. Litvin

Keyword(s):

Electron Gas ◽

Two Dimensional ◽

Dimensional Electron ◽

Two Dimensional Electron Gas ◽

Dimensional Lattice ◽

One Dimensional ◽

Conductance Fluctuations ◽

Dimensional Electron Gas

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Flicker noise in two-dimensional electron gas

Physica Scripta ◽

10.1088/1402-4896/ac3c11 ◽

2021 ◽

Author(s):

Morteza Nattagh Najafi ◽

Susan Tizdast ◽

Zahra Moghaddam ◽

Mahmoud Samadpour

Keyword(s):

Flicker Noise ◽

Electron Gas ◽

Transition Line ◽

Two Dimensional ◽

Dimensional Electron ◽

Scale Invariant ◽

Two Dimensional Electron Gas ◽

Monte Carlo Studies ◽

Dimensional Electron Gas ◽

Electron Coherence

Abstract Using the method developed in a recent paper (Euro. Phys. J. B 92.8 (2019): 1-28) we consider 1/f noise in two-dimensional electron gas (2DEG). The electron coherence length of the system is considered as a basic parameter for discretizing the space, inside which the dynamics of electrons is described by quantum mechanics, while for length scales much larger than it the dynamics is semi-classical. For our model, which is based on the Thomas-Fermi-Dirac approximation, there are two control parameters: temperature T and the disorder strength (∆). Our Monte Carlo studies show that the system exhibits 1/f noise related to the electronic avalanche size, which can serve as a model for describing the experimentally observed ﬂicker noise in 2DEG. The power spectrum of our model scales with frequency with an exponent in the interval 0.3 < αPS < 0.6. We numerically show that the electronic avalanches are scale invariant with power-law behaviors in and out of the metal-insulator transition line.

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CONDUCTANCE FLUCTUATIONS IN A TWO-DIMENSIONAL ELECTRON GAS IN THE TUNNELING AND HOPPING REGIMES

International Journal of Modern Physics B ◽

10.1142/s0217979294000348 ◽

1994 ◽

Vol 08 (07) ◽

pp. 809-817 ◽

Cited By ~ 3

Author(s):

DRAGANA POPOVIĆ ◽

S. WASHBURN ◽

A.B. FOWLER

Keyword(s):

Chemical Potential ◽

Electron Gas ◽

Localized States ◽

Sample Length ◽

Complex Behavior ◽

Two Dimensional ◽

Dimensional Electron ◽

Two Dimensional Electron Gas ◽

Conductance Fluctuations ◽

Dimensional Electron Gas

We report results of low temperature conductance measurements made on a wide two-dimensional electron gas as a function of sample length L and temperature, in a regime where conduction proceeds via tunneling or hopping through channels of localized states. We extend our recent study of the behavior of the ensemble averaged logarithm of conductance <ln G> and focus on fluctuations of conductance as a function of the chemical potential μ, which occur on at least three characteristic gate voltage scales VC. A detailed study of VC and variance vs. L and T for those three types of fluctuations reveals a complex behavior, probably caused by several competing effects. Our results suggest that both disorder and electron-electron interactions have to be taken into account to describe the properties of our samples.

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