Prebreakdown excitation of crystals at double multiphoton resonance: II. Analysis of the effects of transformation of electronic band spectrum

The probabilities of multiphoton transitions between the valence and conduction bands at two-photon resonance on the adjacent transition between two conduction bands are calculated within the three-band model of a crystal. It is shown that, due to the effects of transformation of electronic band spectrum in the field of a strong light wave, the dependence of the multiphoton generation rate of electron-hole pairs on the light intensity j contains ranges where a small change in j leads to an increase in the generation rate of electron-hole pairs by several orders of magnitude, which may increase the number of nonequilibrium carriers to the level sufficient for initiating destruction of the material.