<title>High-order anti-Stokes stimulated Raman scattering with injection techniques</title>

Abstract

We have investigated higher-order anti-Stokes Raman scattering with injection of Stokes or anti-Stokes pulses for the efficient generation of vacuum ultraviolet radiation. Spatial profiles of anti-Stokes pulses were modified and their energies were increased with injection of pulses with the wavelength of the first Stokes pulse to the pump pulse of the fourth harmonic of Nd:YAG laser. Enhancement factors become larger for the higher orders of anti-Stokes pulses. The shift of optimum pressure together with the change of profile from ring to Gaussian-like shape induced by injection explains that the enhancement effect is due to adjustment of phase matching condition for anti-Stokes generation.