Band structure of highly mismatched semiconductor alloys: Coherent potential approximation

Origin of the large band-gap bowing in highly mismatched semiconductor alloys

Valence-band anticrossing in mismatched III-V semiconductor alloys

K. Alberi,1,2 J. Wu,1,2 W. Walukiewicz,1 K. M. Yu,1 O. D. Dubon,1,2 S. P. Watkins,3 C. X. Wang,3 X. Liu,4 Y.-J. Cho,4 and J. Furdyna4 1Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA 2Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA 3Department of Physics, Simon Fraser University, Burna...

Structure of Sn12xGex random alloys as obtained from the coherent potential approximation

The structure of the Sn1 xGex random alloys is studied using density functional theory and the coherent potential approximation. We report on the deviation of the Sn1 xGex alloys from Vegard’s law, addressing their full compositional range. The findings are compared to the related Si1 xGex alloys and to experimental results. Interestingly, the deviation from Vegard’s law is quantitatively and q...

Dipole scattering in highly polar semiconductor alloys

The wide gap polar semiconductors III-V nitrides, II-VI oxides, and ferroelectrics exhibit large spontaneous and piezoelectric polarization due to their nonsymmetric crystal structures. Electrical conductivity in alloys of such crystals is degraded by scattering from the varying polarization coupled to alloy disorder. We have modeled this effect by dipole scattering. We have calculated dipole s...

Effects of Disorder in Mg1−xTaxB2 Alloys using Coherent-Potential Approximation

Using Korringa-Kohn-Rostoker coherent-potential approximation in the atomicsphere approximation (KKR-ASA CPA) method for taking into account the effects of disorder, Gaspari-Gyorffy formalism for calculating the electron-phonon coupling constant λ, and Allen-Dynes equation for calculating Tc, we have studied the variation of Tc in Mg1−xTaxB2 alloys as a function of Ta concentration. Our results...