An optically addressed modulator based on low-temperature-grown multiple quantum well GaAlAs

We report an optically addressed multiple quantum well spatial light modulator with large modulation gain which can be used in applications such as amplified incoherent-to-coherent conversion. The novel device design utilizes separate detector and modulator regions to obtain large gain. The design also incorporates low-temperature-grown quantum wells in the modulator region to reduce the effects of high-intensity readout. Our preliminary data show that modulation gain of 45 and modulation depth of 40% can be obtained by simply applying a dc bias. However, our data also show that the modulation gain decreases at higher writing frequencies, indicating that refreshing the device is required after each write-read operation. © 1997 American Institute of Physics.