Stimulated Raman scattering is an effective means of wavelength conversion and
can largely extend the operating spectral range of an optical source. We demonstrate a highperformance
tunable Raman laser on a sub-micrometer-thick silicon on insulator wafer using a
standard foundry process. The key feature to this laser is the use of a tunable coupling
mechanism to adjust both pump and signal coupling coefficients in the ring cavity, allowing
demonstration of laser emission over a large wavelength tuning range of 83 nm. This Raman
laser demonstrates efficient (slope of up to 26% and a maximum pump-to-signal power
conversion efficiency of 10%) on-chip non-linear wavelength conversion. Our results indicate
great promise for substantially increasing the optical spectral resources available on a silicon
chip
