Intrinsic absorption spectroscopy and related physical quantities of narrow-gap semiconductors Hg_1-xCd_xTe

The intrinsic optical absorption has been measured for thin film samples made from bulk Hg_1-xCd_xTe with x ranging from 0.165 to 0.45 and at temperature from 4.2 to 300 K. The energy gap E_g, momentum matrix P, effective mass of heavy hole and spin-orbit splitting have been obtained from fitting calculations of absorption curves. The temperature coefficient of energy gap versus composition and the energy gap versus composition and temperature have been derived based on the experimental results. The B-M shift, the Urbach absorption tail and the intrinsic carrier concentration n₁ are also discussed in this paper.