A compact cylindrical CO2TEA laser

A cylindrical discharge scheme which utilizes a fine wire as the central electrode is investigated for compact CO2TEA laser applications. It is found that the strong radial dependence of electrical energy deposition into the plasma, a consequence of the large ratio of outer to inner electrode radii, produces a radial gain profile which is well localized in the center of the discharge tube. This allows for efficient matching of low-order stable optical modes to the active gain region while providing a high degree of mode selectivity in favor of these modes. Oscillation in the TEM01Laguerre-Gaussian mode has been obtained at electrical efficiencies approaching 4 percent.