Dielectric function in HgSe at 2, 95, and 300 K

Reflectivity spectra of n‐HgSe with various carrier concentrations are measured in the spectral region 20 to 500 cm −1 . Their main features are well explained by the theoretical dielectric function which is constructed as a sum of Γ 8 –Γ 8 interband, intraband, and phonon contributions and is calculated using the available values of band parameters in the full Kane theory. The effect of the interband contribution on the plasmon–LO phonon coupling and on the frequency of LO phonon is discussed. Possible origins for the discrepancy between experimental and calculated spectra are also discussed.