Third-sound propagation on a periodic substrate

C.A. CONDAT; T.R. KIRKPATRICK

PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS

The American Physical Society

Año: 1985 vol. 32 p. 4392 - 4397

0163-1829

The properties of third-sound propagation on a periodic substrate are predicted. The periodicity is introduced via a regular array of strips of a second substrate. Tha bands of allowed wave numbers k and the corresponding gaps are analyzed for “monatomic” and “diatomic” lattices. The transmission coefficient corresponding to a finite number of regularly distributed strips is also calculated. The introduction of an imperfection in the strip arrangement is seen to lead to efficient transmission for isolated values of k lying inside the gaps. In general, the calculations are elementary and can be carried out exactly.