Optoelectronic bistability at low temperature avalanche breakdown in GaAs epitaxial films

The object of this report is a new type of optoelectronic bistability in n-GaAs epitaxial films at helium temperatures based on the phenomenon of low-temperature impurity breakdown. The bistability mechanism is related with the following two factors: 1. The films possess an S-shaped current-voltage characteristic (CVC) that is light-sensetive (Fig. 1) [ 1] . Light illumination changes the characteristic point Ith, Vao I., V. of the CVC which limit the region of negative differential resistence, here Ith, Va-current and voltage of the threshold points, I., Vi--those of the sustaining points. Under photoexcitation Vlh falls to the value Vtia and Tot increases to Ina . This property of the CVC allows to realize the light-induced electric switching when the external circuit is properly chosen. . _ .•