High-speed 2 × 2 electrically driven spatial light modulator made with GaAs/AlGaAs multiple quantum wells(MQWs)

A 2 × 2 array of individually driven MQW modulators has been fabricated. Because of the large electroabsorption effect in MQWs, good on/off ratios can be achieved in a single pass through a set of 50 MQWs. Each device has an on/off ratio of approximately 1.45 : 1, and the modulator displays rise and fall times of roughly 400 ps.