We are studying Photonic Integrated Circuits.　　　▷Japanese

Variable index arrayed waveguide was fabricated by the III-V semiconductor material. The refractive index in the semiconductor material is changed by thermo-optic effect, plasma effect, and electro-optic effect. If the refractive index of array waveguide is changed, the phase difference between array waveguides are controlled, and wavelength switching characteristics are obtained. The following figure shows the 1x4 wavelength switch by TO effect.



In this wavelength switch, four different wavelength lights are outputted from different ports, this is the wavelength demultiplex operation, and by applying the electric power to the heater, each wavelength lights were switched between output ports. We are fabricating the wavelength switch by using plasma effect or QCSE.