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Magnetic field dependence of conductivity and effective mass of carriers in a model of Mott-Hubbard material

L. Didukh·O. Kramar·Yu. Skorenkyy·Yu. Dovhopyaty
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Abstract

The influence of external magnetic field $h$ on a static conductivity of Mott-Hubbard material which is described by model with correlated hopping of electrons has been investigated. By means of canonical transformation the effective Hamiltonian which takes into account strong intra-site Coulomb repulsion and correlated hopping is obtained. Using a variant of generalized Hartree-Fock approximation the single-electron Green function and quasiparticle energy spectrum of the model have been calculated. The static conductivity $σ$ has been calculated as a function of $h$, electron concentration $n$ and temperature $T$. The correlated hopping is shown to cause the electron-hole asymmetry of transport properties of narrow band materials.

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L. Didukh, O. Kramar, Yu. Skorenkyy, Yu. Dovhopyaty. 2005-08-17. Magnetic field dependence of conductivity and effective mass of carriers in a model of Mott-Hubbard material. https://arxiv.org/abs/cond-mat/0508385

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