  This paper presents a novel principle for photovoltaic (PV) energy conversion
using surface acoustic waves (SAWs) in piezoelectric semiconductors. A SAW
produces a periodically modulated electric potential, which spatially
segregates photoexcited electrons and holes to the maxima and minima of the SAW
potential. The moving SAW collectively transports the carriers with the speed
of sound to the electrodes made of different materials, which extract electrons
and holes separately and generate dc output. The proposed active design is
expected to have higher efficiency than passive designs of the existing PV
devices and to produce enough energy to sustain the SAW.
