Microscopic electronic wave function and interactions between quasiparticles in empirical tight-binding theory

Abstract

International audienceA procedure to obtain single-electron wave functions 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 wave functions. We apply this method to the calculation of the electron-hole exchange interaction, and obtain the dispersion of excitonic fine structure in bulk GaAs. Beyond semiconductor nanostructures, this work is a fundamental step toward modeling many-body effects from post-processing single-particle wave functions within the tight-binding theory

Hyperfine interaction in atomically thin transition metal dichalcogenides

“…The values of the hyperfine interaction constants (A) can be calculated using atomistic approaches, for example DFT [28,69,70]. The orbitals D mz at molybdenum and tungsten are related mainly to the 4d and 5d atomic orbitals, respectively, while the orbitals P mz are related to the 3p, 4p and 5p atomic orbitals at sulfur, selenium and tellurium, respectively.…”

Linear scaling approach for atomistic calculation of excitonic properties of 10-million-atom nanostructures

“…47 By the same token, the spatial extent of basis orbitals in bulk should be reduced as compared with free atoms. This claim has been recently supported by work by Benchamekh et al 76 where microscopic (Bloch) functions for tight-binding model where obtained by a process in which screening constants α of Slater-type orbitals were optimized by the fitting. Ref.…”

“…Ref. 76 shows that the fitting procedure has relatively small effect on well localized 4s and 4p orbitals (sp 3 in tight-binding), e.g. altering 4s screening constant from 1.7 to 1.94.…”

Theoretical analysis of influence of random alloy fluctuations on the optoelectronic properties of site-controlled (111)-oriented InGaAs/GaAs quantum dots

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