Raman laser

In optical fibers made of silica, for example, the frequency shift corresponding to the largest Raman gain is about 13.2 THz.

This significantly lowers threshold pump powers down to practical levels and furthermore enables continuous-wave operation.

Nowadays, commercially available fiber-based Raman lasers can deliver output powers in the range of a few tens of Watts in continuous-wave operation.

In this way, a single laser resonator is used to convert the pump light (typically around 1060 nm) through several discrete steps to an "arbitrary" desired output wavelength.

More recently, Raman lasing has been demonstrated in silicon-based integrated-optical waveguides by Bahram Jalali's group at the University of California in Los Angeles in 2004 (pulsed operation[6]) and by Intel in 2005 (continuous-wave[7]), respectively.