Excitation dynamics during the multiphoton absorption in SF 6+buffer-gas mixtures

Abstract

A detailed analysis of the total average number of absorbed photons 〈 n〉 total during Infrared multiphoton absorption processes in mixtures of SF 6–Ar, N 2 and CH 4 buffer gases is presented. The results for 〈 n〉 total are deduced using pulsed photoacoustic technique in collisional regime. Complete analysis is based on the theoretical generalized coupled two-level model (GCT) and its application to different gas mixtures. Evaluation of partial 〈 n〉 coll. values is presented too, obtained using the results from time-resolved optoacoustic (TROA) and time-resolved absorption (TRA) methods for V–T relaxation times ( τ V–T) and the saturable absorber (SA) method for R,R–T relaxation times ( τ rot.–rel.), and applying them directly to the GCT model. All methods (TROA and SA) and the GCT model use the same photoacoustic results from our experiment under identical experimental conditions.