A high speed 2×2 electro-optic switch using a polarization modulator

A high speed 2x2 electro-optic switch using a polarization modulator (PolM) is proposed and experimentally demonstrated. In the proposed switch, two linearly polarized input lightwaves with orthogonal polarization directions are sent to the PolM which is connected to a polarization beam splitter (PBS). When a switching signal is applied to the PolM, the polarization directions of the two lightwaves at the output of PolM will exchange. Consequently, the lightwaves at the two output ports of the PBS would be switched, a 2x2 switch is thus realized. An optical switch with a crosstalk lower than -35 dB and a switching time less than 25 ps is experimentally demonstrated. The performance of the switch is also experimentally investigated by studying the bit error rates and eye diagrams. A technique to achieve polarization independent operation is also proposed and discussed.