PLASMONS DISPERSION RELATION IN LAYERED SUPERCONDUCTORS AT FINITE TEMPERATURES
Keywords:
Acoustic plasmon, layered superconductors, dispersion relation, retarded polarization, finite temperaturesAbstract
The electronic excitation spectrum for layered conductors has been studied within the random phase approximation (RPA). The plasmon dispersion relation of the layered system at T = 0 has been reported and discussed in earlier works. In this paper we report the effect of the temperature dependence and the inclusion of the leading higher order in wave vector q on the dispersion relation. We show that at low temperature limit the slope of the acoustic plasmon increases significantly due to the inclusion of the higher order in q while the thermal enhancement is nearly negligible. For a high temperature limit the plasmon dispersion relation is shown to be valid only in a very narrow range of the wave vector near zero and agrees quite well with the known classical limit of a two dimensional (2D) system.
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