Photogalvanic effect in asymmetric quantum wells and superlattices

Author： Schneider H. Ehret S. Schonbein C. Schwarz K. Bihlmann G. Fleissner J. Trankle G. Bohm G.

ISSN： 0749-6036

Source： Superlattices and Microstructures, Vol.23, Iss.6, 1998-06, pp. : 1289-1295

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

We have investigated the influence of the final states of bound-to-continuum transitions within the conduction band of asymmetric quantum well structures on the photocurrent. This influence manifests itself by an energy-dependent oscillation of the current direction. We observe pronounced oscillations at zero bias voltage in a double quantum well structure, induced by an asymmetric excitation into continuum states with positive and negative momentum, i.e. by a photogalvanic effect (PGE). If this effect is superimposed on an asymmetric backrelaxation, similar oscillations are observed in the spectrum when the latter asymmetry is compensated by an external electric field. Theoretically, we find a strong relation between the PGE and a quantum interference effect occurring in the continuum.Copyright 1998 Academic Press Limited