Point defect generation by a jog in screw dislocation as a possible reason for the threshold character of ionic crystals sonoluminescence

The threshold character of sonoluminescence excitation of ionic crystals (SLIC) is explained in terms of point defects (PDs) generation. The potential relief for moving jogs in a screw dislocation which generates them is proposed. It depends on the direction of jog motion, or on the energy of the corresponding PD creation. The two critical US amplitudes for jog motion are found. Below the first one the jog proves to be immovable. Between the two critical amplitudes it changes its equilibrium position, having generated a finite number of vacancies. These vacancies then diffuse into the bulk, and can serve as weak pinning centers for dislocations, causing the reduction of US attenuation. The US amplitude above the second critical value causes continuous PD generation, excitation of which by charged dislocations gives rise to SLIC.