Intraband absorption in lead chalcogenide mixed crystals

Abstract

Free carrier absorption due t o the chemical disorder is calculated for lead chalcogenide mixed crystals, taking into account the actual band structure. It is found that in a n alloy the absorption coefficient due to composition fluctuations may be comparable with the intraband absorption due to the LO polar scattering, a t low temperatures.L'absorption des porteurs libres like au dhsordre chimique est calculhe pour les cristaux mixtes des chalcoghures de plomb, tenant compte de la structure rbelle des bandes. On a trouvi. que dans les alliages, le coefficient d'absorption like aux fluctuations de la composition peut 6tre comparable B I'absorption intrabande. dne B la dispersion stir les phonons LO fL basse temperature.