0000000001105641
AUTHOR
P.v. Santos
Embedded interdigital transducers for high frequency surface acoustic waves on GaAs
We investigate high-performance, high-frequency interdigital transducers (IDTs) for the generation of surface acoustic waves(SAWs) on GaAs substrates, where the metal fingers are embedded in the substrate. We demonstrate that the acoustic reflections and the scattering of the surface modes into the substrate become considerably reduced in these transducers, leading to an increased output power. The finger embedding process is particularly relevant for the generation of powerful beams of high-frequency SAWs on weak piezoelectric substrates (such as most of the semiconducting materials) using long IDTs. We also show that the reflection reduction is important for the design of focusing single-finge…
Surface-acoustic-wave-induced space-charge waves in electron–hole systems
Abstract Space-charge waves in an electron–hole system are studied, which are excited by a moving grating provided by a surface acoustic wave (SAW). The SAW induces a constant current that may change its sign, when a constant electric field is applied opposite to the wave propagation direction. Current resonances are predicted to appear, when the SAW wavelength and frequency match the ones of the space-charge wave.