Zero insertion loss operations in monolithically integrated WDM channel selectors

Eight-channel wavelength-division-multiplexed (WDM) channel selectors were fabricated based on an monolithic integration of two arrayed-waveguide gratings and a semiconductor optical amplifier array on InP substrates. A compact device size of 5.2/spl times/3.6 mm/sup 2/ was achieved with a combination of deep-ridge waveguides and buried waveguides. The device can select an arbitrary signal from a WDM signal with a low crosstalk of less than -40 dB, and fiber-to-fiber zero insertion loss operations were also achieved.