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arXiv · 1303.7357

Microscopic Electronic Wavefunction and interactions between quasi particles in Empirical Tight-Binding Theory

R. Benchamekh·F. Raouafi·J. Even·F. Ben Cheikh Larbi·P. Voisin·J. -M. Jancu
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Abstract

A procedure to obtain single-electron wavefunctions within the tight-binding formalism is proposed. It is based on linear combinations of Slater-type orbitals whose screening coefficients are extracted from the optical matrix elements of the tight-binding Hamiltonian. Bloch functions obtained for zinc-blende semiconductors in the extended-basis spds* tight-binding model demonstrate very good agreement with first-principles wavefunctions. We apply this method to the calculation of electron-hole exchange interaction, and obtain the dispersion of excitonic fine structure of bulk GaAs. Beyond semiconductor nanostructures, this work is a fundamental step toward modeling many-body effects from post-processing single particle wavefunctions within the tight-binding theory.

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R. Benchamekh, F. Raouafi, J. Even, F. Ben Cheikh Larbi, P. Voisin, J. -M. Jancu. 2013-03-29. Microscopic Electronic Wavefunction and interactions between quasi particles in Empirical Tight-Binding Theory. https://doi.org/10.1103/physrevb.91.045118

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