Influence of the pump radiation polarisation on the efficiency of pulsed dye lasers

An experimental investigation was made of the dependence of the efficiency of transversely pumped ethanol-solution dye lasers on the orientation of the pump radiation polarisation relative to the optic axis of the laser. The results showed that the output radiation energy of such dye lasers had its maximum value for the pump polarisation oriented along the optic axis, but was independent of the orientation of the output radiation polarisation. A comparison was made of the relative efficiencies of conversion of the pump radiation in a dye laser amplifier for various mutual orientations of the pump and output radiation polarisations. The efficiency of such an amplifier obtained for the collinear and orthogonal (relative to the laser optic axis) polarisations was 1.3–2 times higher than the efficiency obtained for combinations of mutually orthogonal polarisations.