The small signal Raman gain in a single‐mode glass waveguide amplifier has been measured directly. The measured gain is in good agreement with that calculated from the Raman cross section. The cross section was determined by a comparison of the spontaneous Raman scattering of fused quartz and benzene.

Raman gain in glass optical waveguides

Stimulated Raman amplification characteristics in long span single-mode silica fibers

Stimulated Raman Emission in Diamond: Spectrum, Gain, and Angular Distribution of Intensity

Temperature Dependence of Raman Linewidth and Shift inα-Quartz

We report the first observation of tunable stimulated Raman emission. A Q‐switched ruby laser was used to excite the A1 symmetry 248‐cm−1 polariton mode in a LiNbO3 crystal. The crystal, at room temperature, was placed in a resonator external to the laser cavity which was tuned to the Stokes frequency. It was possible to vary the Stokes frequency by altering the angle between the pump beam and the axis of the resonator. Stimulated Raman scattering from other polariton modes (152 cm−1, 628 cm−1) which are potentially tunable was observed. We also report the first observation of stimulated anti‐Stokes emission from a polariton mode.

a Tunable Stimulated Raman Oscillator

Stimulated Raman scattering has been observed in quartz at low temperatures in which the 467 cm−1 Stokes line is split into two or more sharp components. The quartz samples, which were in the form of resonant cavities, behaved as Raman oscillators pumped by a ruby laser. Measurement of the Fabry—Perot mode spacings of the oscillators showed that substantial mode pulling was occurring. This was interpreted according to mode‐pulling theory.

P. E. Tannenwald

Papers

Mode Pulling in a Stimulated Raman Oscillator