Voltage-controlled optical bistability associated with two-dimensional exciton in GaAs-AlGaAs multiple quantum well lasers

Voltage-controlled optical bistable laser operation is demonstrated for the first time using nonlinear optical absorption of two-dimensional excitons in a GaAs-AlGaAs multiple quantum well (MQW) laser. The laser used here is the conventional MQW laser diode but with tandem electrode configuration. The L-I curve of light output as a function of current injected into one segment of electrodes can be changed by a bias voltage applied to the other segment of electrodes. At the onset of laser oscillation, a hysteresis loop appears, the shape of which depends strongly on the applied bias voltage. This bistability is ascribed to the nonlinear absorption of two-dimensional excitons.