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arXiv · 1610.05829

First and second-order metal-insulator phase transitions and topological aspects of a Hubbard-Rashba system

Edgar Marcelino
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Abstract

This paper considers a model consisting of a kinetic term, Rashba spin-orbit coupling and short-range Coulomb interaction at zero-temperature. The Coulomb interaction is decoupled by a mean-field approximation in the spin channel using field theory methods. The results feature a first-order phase transition for any finite value of the chemical potential and quantum criticality for vanishing chemical potential. The Hall conductivity is also computed using Kubo formula in a mean-field effective Hamiltonian. In the limit of infinite mass the kinetic term vanishes and all the phase transitions are of second order, in this case spontaneous symmetry breaking mechanism adds a ferromagnetic metallic phase to the system and features a zero-temperature quantization of the Hall conductivity in the insulating one.

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Edgar Marcelino. 2017-11-07. First and second-order metal-insulator phase transitions and topological aspects of a Hubbard-Rashba system. https://doi.org/10.1103/physrevb.95.195112

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