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Microscopic mechanisms of dephasing due to electron-electron interactions

R. Zitko·J. Bonca
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Abstract

We develop a non-perturbative numerical method to study tunneling of a single electron through an Aharonov-Bohm ring where several strongly interacting electrons are bound. Inelastic processes and spin-flip scattering are taken into account. The method is applied to study microscopic mechanisms of dephasing in a non-trivial model. We show that electron-electron interactions described by the Hubbard Hamiltonian lead to strong dephasing: the transmission probability at flux $Φ=π$ is high even at small interaction strength. In addition to inelastic scattering, we identify two energy conserving mechanisms of dephasing: symmetry-changing and spin-flip scattering. The many-electron state on the ring determines which of these mechanisms will be at play: transmitted current can occur either in elastic or inelastic channels, with or without changing the spin of the scattering electron.

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R. Zitko, J. Bonca. 2003-05-15. Microscopic mechanisms of dephasing due to electron-electron interactions. https://doi.org/10.1103/physrevb.68.085313

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