Temperature Dependence of the Electron Raman Light Scattering in Normal Metals and Superconductors

Abstract

The discovery of high-temperature superconductors has led to an increase of interest in electron light scattering. In this class of substances a thresholdless of electronic Raman light scattering is observed. In the range w « 2Δ (ω = ωi —'ωs , where ωi (ωs) is the frequency of incident (scattered) light) the linear dependence of scattering cross-section on w is observed. This can be caused, e.g., by spatial inhomogeneities in the energy gap (2Δ) in the sample and/or the type of electron pairing leading to the vanishing of the gap on the lines [1] or points on the Fermi surface. By now, the role of local heating by laser spot in a system with small heat conduction remains unclear, although there exists a relatively simple way of measuring the temperature basing on the peak-to-peak Stokes I(ω) and anti-Stokes I(—ω) intensities distance. It holds I(—ω) = I(ω) exp —hω/kT). This paper is devoted to investigations of the effect of temperature on electronic light scattering in an anisotropic metal in normal and superconducting state.