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arXiv · 1302.6062

Quantum transport equations for low-dimensional multiband electronic systems. I

I. Kupcic·Z. Rukelj·S. Barisic
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Abstract

A systematic method of calculating the dynamical conductivity tensor in a general multiband electronic model with strong boson-mediated electron-electron interactions is described. The theory is based on the exact semiclassical expression for the coupling between valence electrons and electromagnetic fields and on the self-consistent Bethe--Salpeter equations for the electron-hole propagators. The general diagrammatic perturbation expressions for the intraband and interband single-particle conductivity are determined. The relations between the intraband Bethe--Salpeter equation, the quantum transport equation and the ordinary transport equation are briefly discussed within the memory-function approximation. The effects of the Lorentz dipole-dipole interactions on the dynamical conductivity of low-dimensional $sp_α$ models are described in the same approximation. Such formalism proves useful in studies of different (pseudo)gapped states of quasi-one-dimensional systems with the metal-to-insulator phase transitions and can be easily extended to underdoped two-dimensional high-$T_c$ superconductors.

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I. Kupcic, Z. Rukelj, S. Barisic. 2013-02-25. Quantum transport equations for low-dimensional multiband electronic systems. I. https://doi.org/10.1088/0953-8984%2F25%2F14%2F145602

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