Acoustoelectric Aftercurrents in Photoconducting CdS

Abstract

Two aspects of the acoustoelectric aftercurrent in photoconducting CdS are investigated. First, the value of the aftercurrent immediately after the voltage is removed (the maximum aftercurrent) is considered. A linear model is shown to predict that the maximum aftercurrent is proportional to the difference between the ohmic current and the current just before the voltage is removed. The experimental results show good qualitative agreement with this prediction. Secondly, the time behavior of the aftercurrent is considered. The persistence time of the aftercurrent is found to be dependent on the maximum aftercurrent in agreement with the predictions of the model.

Acoustoelectric interaction in semiconductors

“…Relative acoustic intensity W/W, revealed by BS as a function of time t after termination of the applied field Eo (1 kV/cm; f = 400 MHz). For the two upper curves a bias field Eb was applied subsequently to the drift field E, (after Ishida and Inuishi [and has recently been discussed by Neudorfer and Yee[153]. This effect is due to the finite time the enhanced acoustic flux needs to return to thermal equilibrium.…”