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Journal of Physics and Chemistry of Solids

Finite temperature theory for the attenuation of quasi-particle excitations in real metals

R. W. Davies

Published Jun 1, 1967• 1 citation
Publisher
DOI
10.1016/0022-3697(67)90217-x

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We present a simple and efficient method to calculate the damping for the excitation spectrum of a uniform D-dimensional Bose gas. Starting from the original Popov's hydrodynamic description and integrating out phase variables, we obtained the effective action of amplitude fluctuations. Within this approach, the lifetime of quasi-particles with a finite momentum is calculated at a wide temperature range. It is shown that the correct use of the hydrodynamic approach leads to the damping rate, which coincides with results obtained by means of the perturbation theory.