Self-consistent temperature waves in Fermi glasses with thermally activated conductivity.

Abstract

The basic equations of the presented model are the Maxwell heat-conduction equation, the kinetic equation for the thermally activated carriers in Fermi glasses, and the Gauss equation. Assuming, that the temperature and the concentration of the thermally activated carriers may be divided into equilibrium and nonequilibrium parts and that the electric field consists of constant and variable parts, the system of equations is linearized. It is shown that it possesses solutions in the form of nondamped self-consistent temperature waves (STW's) similar to second-sound waves. These solutions are analyzed and it is shown that STW's exist down to some limiting frequency. Numerical calculations are performed for the Fermi-glass phase of ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$.