Composition and temperature dependence of the refractive index in Hg1−xCdxTe

摘要

The intrinsic absorption spectra for very thin Hg1−xCdxTe bulk samples with compositionsxranging from 0.276 to 0.443 have been obtained at different temperatures. Based on the measured absorption curves and Kramers–Kronig relation, the refractive index dispersion has been calculated in the wavelength region near and below the band gap at temperatures from 4.2 to 300 K. For Hg1−xCdxTe samples withxfrom 0.276 to 0.443, the dispersion relation can be described by an empirical formula:n(lgr;,T)2=A+B/1−(C/lgr;)2+Dlgr;2, where the parametersA,B,C, andDare both temperature and composition dependent. In addition, a peak in the deduced dispersion spectra appears just at the wavelength corresponding to the band‐gap energyEg(x,T) of Hg1−xCdxTe.