Narrowband gain saturation characteristics in XeF lasers.

Presented are the gain characteristics of an electron-beam pumped XeF gas mixture (neon diluent) while saturating with either one or two external laser beams whose wavelengths are various combinations of the XeF laser lines (i.e., 351.1, 351.2, and 353.2 nm). Individual saturating beam fluxes ranged from <1 to approximately 6 MW/cm(2), with bandwidths of either 4 or 8 GHz. A third broadband UV dye laser probes the laser medium to measure the total XeF gain spectrum during saturation. The electron-beam deposition rate is either 270 or 380 kW/cm(3) and the gas temperature is 400 K. The results indicate that rotational coupling within the XeF gain band for each of the laser lines is relatively fast and saturation appears fairly homogeneous. However, vibrational coupling between the laser lines appears to be nonuniform and not as strong. The saturation behavior is relatively insensitive to the saturation beam bandwidths investigated, indicating that efficient narrowband extraction within a gain band may be possible. Due to the weak vibrational coupling, efficient extraction from the XeF manifold probably requires extraction on at least two of the laser lines. Results with neon and argon diluent at 294 K are also presented.