Experimental study of a ring dye laser with an external retroreflecting mirror

We have experimentally studied the forward-to-backward intracavity intensity ratios for a rhodamine 6G ring dye laser with an external retroreflecting mirror. The experiments were conducted at several wavelengths, degrees of excitation, and cavity configurations. The results indicate the large forward-to-backward ratios are only achievable near threshold and that this method is not suitable for the elimination of susceptibility gratings in the medium.