Abstract

One of the most interesting features of stimulated rotational Raman scattering (SRRS) is the influence of polarization of a pump wave on gain coefficients of Stokes and anti-Stokes waves.¹ In a diatomic gas, when a circularly polarized laser beam is used as a pump, only the Stokes wave with the counter rotation of circular polarization is scattered in the forward direction. When an incident beam is linearly polarized, the parametric coupling is maximum and totally suppresses the growth of both of the Stokes and anti-Stokes waves. On the contrary, an elliptically polarized pump beam allows growth of anti-Stokes wave by parametric four-wave mixing (FWM). However, photon conversion efficiency of anti-Stokes generation by the FWM process can not exceed 50% because stimulated Stokes process (SSP) is dominant at Raman resonance.

© 1988 Optical Society of America