Nonlinear Screening in Two-Dimensional Electron Gases

Nonlinear screening in two-dimensional electron gases.

We have performed self-consistent calculations of the nonlinear screening of a point charge Z in a two-dimensional electron gas using a density functional theory method. We find that the screened potential for a Z=1 charge supports a bound state even in the high-density limit where one might expect perturbation theory to apply. To explain this behavior, we prove a theorem to show that the resul...

Nonlinear screening and stopping power in two-dimensional electron gases

We have used density-functional theory to study the nonlinear screening properties of a two-dimensional s2Dd electron gas. In particular, we consider the screening of an external static point charge of magnitude Z as a function of the distance of the charge from the plane of the gas. The self-consistent screening potentials are then used to determine the 2D stopping power in the low-velocity li...

Tunneling between parallel two-dimensional electron gases.

The tunneling between two parallel two-dimensional electron gases has been investigated as a function of temperature T , carrier density n, and the applied perpendicular magnetic field B. In zero magnetic field the equilibrium resonant lineshape is Lorentzian, reflecting the Lorentzian form of the spectral functions within each layer. From the width of the tunneling resonance the lifetime of th...

InGaAs/GaAsSb based two-dimensional electron gases

Electron Transport in III-V Nitride Two-Dimensional Electron Gases

We present a study of electron scattering processes in AlGaN/GaN two-dimensional electron gases. A theoretical study of the effect of deformation potential scattering from strain fields surrounding dislocations is presented. The most important scattering mechanisms limiting electron transport are identified. We find that for AlGaN/GaN 2DEGs, mobility is limited by alloy scattering at high 2DEG ...