ELECTROTHERMAL INSTABILITIES INDUCED BY A METASTABLE ELECTRONIC-STATEIN PBTE(GA)

The electrothermal instabilities in high-resistance single crystals of PbTe(Ga) irradiated by infrared light are described phenomenologicall y. Instabilities show up in the form of periodic oscillations in the c urrent in the sample circuit and in its temperature in sufficiently hi gh electric fields. For observation of these phenomena it is important that the energy spectrum of the semiconductor contain metastable elec tronic states lying about 20 meV below the bottom of the conduction ba nd. (C) 1997 American Institute of Physics.