Intrinsic Optical Absorption and the Radiative Recombination Lifetime in PbS

Abstract

The intrinsic optical absorption spectrum of PbS crystals has been measured. The absorption coefficients range from about 10 ${\mathrm{cm}}^{\ensuremath{-}1}$ to ${10}^{5}$ ${\mathrm{cm}}^{\ensuremath{-}1}$ giving continuous data through the band edge. At 300\ifmmode^\circ\else\textdegree\fi{}K the data indicate a direct transition energy of 0.41 ev and an indirect transition energy of 0.37 ev. The radiative recombination lifetime for PbS calculated from the absorption data is 63 microseconds at 300\ifmmode^\circ\else\textdegree\fi{}K.