Thermal breakdown, bistability, and complex high-frequency current oscillations due to carrier heating in superlattices

Abstract

The impact of electron heating on vertical electrical transport in superlattices is shown to cause an S-shaped current-voltage characteristic in addition to the conventional N type occurring at lower fields. Our calculations are supported by experimental data. The combination of S- and N-type instabilities leads to a modified structure of the high-field domains associated with self-generated GHz oscillations. (C) 2000 American Institute of Physics. [S0003-6951(00)00315-6].