Rate equations for modelling of short-pulse rare-gas halide excimer lasers

Abstract

In this work, on the basis of the analysis of data relating to relaxation processes and emission spectra of excimer molecules, the rate equations for modelling short-pulse rare-gas halide excimer lasers are formulated and discussed. The equations take into account relaxation processes important for short-pulse generation, such as decay of B-, C-and X-states, vibrational relaxation in these states, and B-C mixing. As a special case for these equations, simplified equations for KrF and XeCI lasers are introduced. The gain recovery curves and the dependences of saturation energy on pulse duration, computed both for KrF and XeCI, coincide well with the experimental data. Discussion of the factors influencing the gain dynamics and the saturation energy of these media, is also presented.

Theoretical study of amplified spontaneous emission using a model based on a geometrically dependent gain coefficient

“…σ ν 0 stim = 2.6 × 10 −16 cm 2 [30], and σ ν 0 stim τ sp = 1.75 × 10 −24 cm 2 s [17]. These two values give τ sp = 6.7 ns, where it is also given in [31]. ν 0 is calculated to be 8.94 × 10 12 Hz ( λ 0 = 18.40 Å) which is close to the measured value.…”