Observation of the bistable current-voltage characteristics in the highly doped multi-quantum well heterostructure

A new switching behavior was observed in current-voltage (I-V) characterist ics of n(+)-doped multi-quantum wells (MQW's) heterostructure inserted betw een n(+) cathode and p(+) anode layer. The I-V characteristics exhibited a bistability of the low conductance state below the threshold voltage as wel l as the high conductance state at and above the threshold voltage. The hig h conductance state especially was sustained even when the bias voltage swe pt back to a small voltage less than the threshold voltage. The bistability is attributed to the electron confinement within the quantum wells and the ejection of the confined electrons from the wells through the impact ioniz ation.