Using tungsten oxide based thin films for optical memory and the effects of using IR combined with blue/blue-green wavelengths

Utilizing a form of tungsten oxide as the physical medium for optical memor y, we show that infrared irradiation provides heat to the lattice structure while blue or blue-green light provides electronic excitation to initiate a photochromic chemical change. We have constructed and tested a spin stand based demonstration system for this form of optical memory. Tungsten oxide offers potential advantages in storage density, storage capacity, write sp eed, signal to noise, processing flexibility, data robustness, and overall, cost.