Intracenter Raman silicon lasers

Abstract

Raman-type Stokes stimulated emission in the far-infrared wavelength range (52–65 μm) has been realized in silicon crystals doped by group-V hydrogen-like donor centers at low temperatures under optical excitation by radiation from a pulsed frequency-tunable infrared free-electron laser. The light scattering appears as an entire intracenter process and occurs on the donor electronic transitions being resonant to the intervalley transverse acoustic g phonon. The outgoing and incoming electronic donor resonances amplify the efficiency of scattering, so that the Raman optical gain increases to the values observed for the infrared room temperature Raman silicon lasers.