Light-induced index change in a waveguide of a novel organic quinoid dye and its applications to all-optical devices with localized nonlinearity

We have studied optical nonlinearities in a waveguide fabricated from a thin film of a novel quinoid dye and conventional glass materials, and reported a light-induced phase shift of over 2/spl Pi/ with a response time below 10 ps in the waveguide. However, there was a large insertion loss over 20dB in the waveguide of 25mm length, which may become a problem for applications to all-optical functional devices. Here, we report an improvement of the propagation characteristics and further measurements of the nonlinearity in the quinoid dye waveguide. Applications to all-optical devices are also discussed.