Three-Dimensional Quantum Transport Simulations of Transmission Fluctuations in a Quantum Dot

Abstract

Semiconductor nanostructures exhibiting reduced dimensionality, such as quantum wells, wires and dots, have recently drawn much attention. With characteristic dimensions comparable to the electron de Broglie wavelength, these structures operate in the quantum regime and are sensitive to atomic scale variations in geometry and composition. Defect impurities and interface roughness, for example, can alter transport properties (e. g. Mitin, 1990; McEuen et al., 1990; Eugster et al., 1992; Bagwell, 1991; Nixon and Baranger, 1991). In this paper we employ the planar supercell stack method (Kirby et al., 1993, Ting et al., 1993) to study sample to sample transmission resonance fluctuations resulting from variations in interface roughness and neutral impurities in a quantum dot electron waveguide.