Direct observation of the path of ultrasound wave propagation in AgCl crystals by the "print-out effect"

Abstract

The effect of ultrasound waves on the "print-out effect" in AgCl cystals was studied at room temperature. When a longitudinal stationary ultrasound wave existed in crystals subjected to electric field and light pulses, black planes caused by the print-out effect were produced. These planes were located perpendicular to the direction of the wave propagation. The distance between the darkened planes roughly equaled a half-wavelength of the ultrasound. They were arranged in nodal planes. It is concluded that these planes are the result of a print-out effect due to fresh dislocation moved by the shear stress of stationary longitudinal waves. The trace of the ultrasound wave propagation was directly observed by the darkening, which is the first direct observation of the wave propagation trace in solids. The effect of a traveling wave on the print-out effect was not observed.