Abstract

An all-optical self-routing (OSR) crossbar switch that employs tag light with wavelength-encoded address,¹ is experimentally demonstrated by using a fast GaAs-pin/ferroelectric-liquid-crystal spatial light modulator (FLC-SLM) as the switching device. The switch consists of the SLM and bandpass filters in front of it. The optical packet consists of information light along with the tag light. Each bandpass filter passes both information light and only one of the tag lights with a specific wavelength. The tag light passing the filter activates a part of the SLM. Then the information light is allowed to pass through the modulated position of SLM and routed to a preassigned output port. A fast optically addressable GaAspin/FLC-SLM is developed as a switching device. It consists of pixelized GaAs p-i-n photodiode as photodetector and FLC as modulator. The FLC modulates 1.3-μm readout light with a short wavelength (0.6 ~ 0.83μm) writing beam. Rise times (10-90%) of 86 psec and fall time of 98 psec are obtained. The 2 × 2 switching experiment was successfully carried out using tag LDs of 0.67 μm and 0.78 μm. Using a current SLM and a LD light source, up to 10² × 10² OSR crossbar switching will be possible with response time ~100 psec.

© 1991 Optical Society of America