Selective Transmission of High-Frequency Phonons by a Superlattice: The "Dielectric" Phonon Filter

Abstract

The zone folding in the acoustic-phonon dispersion curve of GaAs/AlGaAs superlattices is demonstrated using superconducting tunnel junctions as sources and detectors of quasimonochromatic phonons. We present data on selective transmission of high-frequency phonons due to narrow band reflection determined by the superlattice period.