Modeling the optical constants of HgxCd1-xTe alloys in the 1.5-6.0 eV range

The optical constants of HgxCd1-xTe as a function of energy and composition x are modeled over a wide spectral range from 1.5 to 6 eV. The model emplo yed represents an extension of Adachi's model and incorporates the adjustab le broadening function rather than the conventional Lorentzian one. In this way, greater flexibility of the model is achieved, enabling us to obtain a n excellent agreement with the experimental data. The relative rms errors o btained for all compositions are below 2.5% for the real part and below 6% for the imaginary part of the index of refraction. The lowest rms errors ar e obtained for x = 0 (0.6% for the real part and 0.7% for the imaginary par t of the index of refraction!, and the highest for the x = 0.91 (2.4% for t he real part and 5.8% for the imaginary part). (C) 1999 American Institute of Physics. [S0021-8979(99)05105-1].