Abstract

Compound semiconductors, such as GaAs and InP, are potential photo- refractive materials for real-time volume holographic elements in optical computing applications. The advantages of these photorefractive compound semiconductors include fast response^1,2 (now down to picoseconds³), high sensitivity^1,4, reconfigurability, high degree of parallelism, and operation at infrared wavelengths compatible with semiconductor lasers⁵ as well as VLSI technology. Recently, Cheng and Partovi⁴ investigated temperature and intensity dependence of photorefractive effect in semi-insulating, Cr-doped GaAs, revealing some operation characteristics for the semiconductor as a practical device. For example, at room temperature, minimum beam intensities of about 10 mW/cm² are needed to form index gratings of near-saturation amplitudes, but the requirement increases to about 100 mW/cm² at 50°C. This is due to the competing effects of the dark and light-induced electrical conductivities.

© 1987 Optical Society of America