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) characteristics of n/sup +/-doped multi-quantum wells (MQW's) heterostructure inserted between n/sup +/ cathode and p/sup +/ anode layer. The I-V characteristics exhibited a bistability of the low conductance state below the threshold voltage as well as the high conductance state at and above the threshold voltage. The high conductance state especially was sustained even when the bias voltage swept 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 ionization.