Abstract

Recent reports have described the use of semi-insulating multiple quantum well structures as optically addressed spatial light modulators. SIMQW devices have been reported that use both the quantum confined Stark effect and the Franz-Keldysh effect to produce the excitonic electro-absorption.^1,2 Both types of devices utilize optically produced free carriers to screen out an applied ac field and thereby spatially modulate the exciton absorption near the band edge. The large dark resistivities of these structures allow them to support high resolution absorption gratings which are erased with the reversal of the applied field. Such devices are read out with simple Raman-Nath scattering of a low power probe laser tuned near the excitonic resonance.

© 1994 Optical Society of America