Band Structure and Optical Properties οf the Layered Hg₃TeCl₄Crystal

Abstract

First experimental investigations on absorption and photoluminescence of the novel Hg3TeCl4 monocrystals grown by the Bridgman method are reported. A comparison of the measurement results with theoretical band structure calculations of the Hg3TeCl4 crystal confirmed that Hg3TeCl4 is a wide-band-gap photoconductor (Eg = 3.64 eV at 24 K) with the effective masses of charge carriers characteristic for semiconductors. Energetic position of the main photoluminescence peak and its temperature dependence indicates the presence of an additional energy level in the energy gap which takes part in the radiative recombination process and whose origin was discussed.