A 1×3 optical switch by carrier induced beam-steering on InP

We demonstrate an integrated 1x3 optical switch that operates using the principle of carrier-induced refractive index change in InGaAsP multiple quantum wells. The core of the switch relies on a beam-steering concept which allows us to steer the optical beam to any of three output waveguides. The device is relatively simple, since current is only applied to two electrodes for complete operational control. The device integration is achieved using an area-selective zinc in-diffusion process that is used to channel the currents into the multiple quantum wells, thereby enhancing the efficiency of the carrier-induced effects. This results in a low electrical power consumption, allowing the switch to be operated uncooled and under d.c. current conditions. The crosstalk between channels is better than -17 dB over a range of 50 nm centered at 1565 nm.