Multifrequency laser having integrated amplified output coupler for high-extinction-ratio modulation with single-mode behavior

We present a 16-channel waveguide grating router multifrequency laser that can be modulated with a 250-MHz bandwidth, a 50-dB extinction ratio, and constant single-mode behavior. We demonstrate a means for immunizing the singlemode lasing against unwanted backreflections from the integrated modulation amplifier. The laser is especially suitable for fiber dispersion-map measurements.