The damage and transmission properties of selected commercially available fused silica fibers have been measured as a function of excimer laser wavelength. Two-photon absorption and color center formation in fused silica currently limit the use of these fibers at the excimer wavelengths of 193 nm (ArF) and 248 nm (KrF).

The nonlinear transmission properties of commercially available fused silica fibers have been determined as a function of excimer laser wavelength. Accurate two-photon absorption coefficients have been measured and the influence of color center formation is discussed. Two-photon absorption and color center formation dominate the ArF and KrF transmission at high intensities while both of these effects are negligible at the XeCl and XeF laser wavelengths.

Experimental results are presented which show that the dynamic Stark effect significantly reduces the small-signal gain (in discharge-excited CO2) and absorption (in unexcited CO2) at the line center of 4.3-μm laser lines directly coupled to 10.4-μm sequence-band pump transitions. In unexcited CO2, population transfer by the pump radiation is negligible and the influence of coherent effects can be observed unambiguously. The results of comparing experiment and theory in this simple case are used to modify a rate-equation model of the 4.3-μm gain dynamics, and the modified calculations are shown to be in good agreement with measured 4.3-μm gain coefficients.

No abstract

No abstract