InGaAs/InAlAs bistable multiple quantum well lasers with large on/off ratio using the resonant tunneling effect

Bistable operation with a large on/off ratio of 800:1 is achieved in InGaAs/InAlAs multiple quantum well (MQW) lasers using the resonant tunneling effect at 77 K. Structural dependence of resonant tunneling characteristic in the MQW structures reveals that the threshold current density, at which negative differential resistance appears, increases drastically when the InAlAs barrier width of MQW structures decreases. The increase in the threshold current density has led to an improvement in the bistable characteristics of InGaAs/InAlAs MQW lasers.