Acoustoelectric domain propagation in two-dimensional photoconducting CdS

It is known that the initial saturation of current and subsequent current oscillations in photoconducting CdS is caused by the presence of high electric field domains traveling at the acoustic shear-wave velocity. The behavior of travel ing domains in nonuniform two-dimensional CdS samples is here studied for the first time. Experimental data showing both the uniform domain propagation in homogeneous region and the nonuniform domain propagation in inhomogeneous region of the two-dimensional samples reveal that domain formation and propagation are consistent with the acoustoelectric model. Local domains originating from the inhomogeneous part of the sample do not propagate in the direction of the applied field and thus may increase the effective traveling path.