Photoresponse on Surface Acoustic Wave Devices with Compound Semiconductor and LiNbO₃ Structures

Abstract

We studied the photoresponse on a surface acoustic wave (SAW) device coupled with AlGaAs film. The experimental results indicate that the transferred carriers by SAW are optically generated electrons rather than optically generated holes. The electric field due to SAW propagation reduces the recombination of the optically generated electrons and holes. We were able to observed a modulated SAW signal due to the nonlinear interaction between SAW and optically induced carriers. The photoresponse due to the interaction between SAW and optically induced carriers shows a high sensitivity for the light intensity. The main results are (1) the control of SAW by optically induced carriers, and (2) the control of the optically induced carriers by SAW. We expect that the characteristics of the photoresponse will be applicable to the fabrication of functional optical-SAW coupled devices.