Reflection-type space-division optical switch based on the electrically tuned Goos-Hanchen effect

A reflection-type space-division optical switch is theoretically proposed and experimentally demonstrated based on the electrically tuned Goos-Hanchen effect in a symmetrical metal-cladding waveguide which employs the PMN-PT ceramics as the guiding layer. Owing to the high sensitivity of the ultrahigh-order modes, the variation of refractive index and thickness induced by the exertion of the controlled voltage on the PMN-PT ceramics will easily give rise to a change in the position of the reflected light. In the experiment, a three-pinhole array is put in the reflected light path and a one-to-three optical switch is achieved. The switching time for 10%-90% light intensity change and the optical crosstalk are measured to be lower than 1.63 mu s and -29 dB, respectively. Since the Goos-Hanchen shift can reach approximately 1 mm, the number of output ports can be further increased on condition that the utilized incident light has a smaller spot diameter.