Dynamical conductivity of PbTe in the frequency range of LO-phonon—plasmon excitations

Abstract
A strong resonantlike increase of the electron damping parameter was observed in the region of the coupled LO-phonon-plasmon excitations in n-PbTe at low temperatures. This behavior is interpreted as evidence of a generation of collective coupled plasmon-phonon excitations. The experimental results can be interpreted very well by a model calculation as reported recently by Mycielski et al.