Article

First-principles Study on the Electronic Structures and the Optical Properties of Hg(1-x)Cd(x)Te

Journal- Korean Physical Society (Impact Factor: 0.42). 04/2010; 56(41):1307-1310. DOI: 10.3938/jkps.56.1307

ABSTRACT

The electronic structures and the optical properties of the direct-band-gap infrared alloy Hg(1-x)Cd(x)Te (x = 0.250, 0.375, 0.500, 0.625, 0.875, and 1.000) were obtained using the local spin density approximation (LSDA) in the density functional theory (PET). The calculated lattice constants are in agreement with these calculated using Vergard's law and the band structures of these alloys are similar. The three peaks of the imaginary part in the dielectric function reveal that the conduction bands lift with increasing a. The calculated static dielectric constants of these alloys were shown to behave as a parabolic function. The results for the loss functions and effective electronic densities show that few electrons take part in the interband transitions.

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