Polarization-independent dilated InP-based space switch with low crosstalk

A polarization-independent dilated switch with a low crosstalk level has been realized. In this switch, the crosstalk signal is attenuated by using controllable electrooptical attenuators which do not disturb the input signal. A reverse bias of 20 V on the attenuators reduces the crosstalk value of the dilated switch from -32 dB to -40 dB. The excess loss of the total switch is about 9 dB.