2$\,\times\,$ 2 InP Optical Switching Matrix Based on Carrier-Induced Effects for 1.55-$\mu$m Applications

This letter demonstrates a 2times2 low optical crosstalk and low power consumption switching matrix device based on carrier-induced effects on an InP substrate. The matrix device comprises two digital optical switches (DOSs) with a wide multimode Y-junction associated with a sinusoidal passive integrated optical circuit with an optimized X-crossing. The passive structure was designed using a two-dimensional beam propagation method (BPM) and the entire InP-InGaAsP-InP DOS was designed using a semivectorial three-dimensional BPM. The fabricated 2times2 InP switching matrix heterostructure with lambda
g
=1.3 mum exhibits optical crosstalk as low as -30.5 dB for drive current of 52 mA at 1.55-mum wavelength. Maximum crosstalk change of 4 dB is measured under optical polarization variation.