Physical Review B (Brief Reports) 52, 13788 (1995)

Probing growth-related disorder by high-field transport in semiconductor superlattices

A. Wacker, G. Schwarz, F. Prengel, and E. Schöll

Institut für Theoretische Physik, Technische Universität Berlin,
Hardenbergstrasse 36, 10623 Berlin, Germany

J. Kastrup and H. T. Grahn

Paul-Drude-Institut für Festkörperelektronik,
Hausvogteiplatz 5-7, 10117 Berlin, Germany

Abstract

We investigate the influence of imperfections in the sample growth on the electrical transport in doped superlattices. While structurally perfect samples should exhibit a regular set of current branches, our theoretical investigations show that local fluctuations of the sample parameters in the growth direction strongly modulate the branches of the current-voltage characteristic. A comparison with experimental data allows an estimate of the range of doping fluctuations between 3 and 10 %. The disorder strongly affects the frequency as well as the mode of the self-oscillations of the current.

PACS number: 72.20.Ht, 68.65.+g

mail:schwarz@physik.tu-berlin.de

last update: Nov 10, 1995