Phonon scattering at plane interfaces and surfaces

Abstract

Phonon pulses propagate with group velocity. Therefore, the concept of group velocity is discussed in the range of continuum acoustics and in the general frame of lattice dynamics, too. The rather complicated problem of phonon reflection and refraction at a plane boundary is presented with the help of frequency surfaces in 'q-space. This treatment emphasizes the underlying geometrical properties and gives an understanding of the excited wavemodes. The explicit determination of the phonon-scattering probabilities requires extensive numerical computation.