Description:
<jats:title>Abstract</jats:title><jats:p>In lead chalcogenides with degenerate statistics the small‐signal lifetime for spontaneous emission of phonon–plasmon coupled modes is calculated in dependence on temperature. The results are compared with corresponding data concerning Auger recombination. Within the approximation of undamped collective modes plasmon emission dominates as compared to Auger recombination for doping levels <jats:italic>N</jats:italic><jats:sub>D</jats:sub> > 10<jats:sup>19</jats:sup> cm<jats:sup>−3</jats:sup> in PbSnSe at sufficiently low temperatures.</jats:p>