Propagation of fast leaky surface waves in a system of metal electrodes ona lithium tetraborate crystal

Dispersion curves are calculated for fast leaky surface acoustic waves in a periodic system of metal electrodes on a lithium tetraborate crystal. The periodic Green's function analysis is applied to the piezoelectric halfspac e. To allow for the mechanical properties of the electrodes, a perturbation method is developed that is accurate to within the first order of the elec trode thickness-to-period ratio, and the finite-element method is used to i nvestigate the higher-order effects. The reflection factor of a system of t wo open electrodes is shown to have a minimum at a certain electrode thickn ess. The fast leaky-to-Rayleigh wave conversion factor and the Rayleigh wav e reflection factor are studied as functions of the electrode thickness. (C ) 2000 MAIK "Nauka/Interperiodica".