TUNABLE SAMPLED-GRATING DBR LASERS WITH INTEGRATED WAVELENGTH MONITORS

We report on the design and development of a wavelength monitor for us e with tunable semiconductor lasers. The device is based on two-mode i nterference in an asymmetrically excited waveguide that is coupled to a Y-branch splitter. The monitoring range of the device is 30 mn, The wavelength monitor is capable of operating over an input power range o f 34 dB, and the waveguide detectors do not saturate at photocurrents as high as 1.2 mA. The sensitivity of the monitor is only 1.24 mm for an isolated device, but improves to 0.44 nm when it is integrated on c hip with the laser.