Multifrequency Laser with Reduced Intracavity Wave Mixing

We demonstrate a 10-channel, 100-GHz spacing, waveguide grating router multifrequency laser that has significantly reduced intracavity wave mixing. The mixing products for the improved design are now too small to cause significant laser fluctuations during simultaneous multichannel operation. This was accomplished by reducing the shared waveguide length to 150 microns. We provide evidence that a significant portion of the remaining wave mixing occurs in the intracavity waveguide grating arms.