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arXiv · 1504.08314

Temperature-induced spontaneous time-reversal symmetry breaking on the honeycomb lattice

Wei Liu·Alexander Punnoose
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Abstract

Phase transitions involving spontaneous time-reversal symmetry breaking are studied on the honeycomb lattice at finite hole-doping with next-nearest-neighbor repulsion. We derive an exact expression for the mean-field equation of state in closed form, valid at temperatures much less than the Fermi energy. Contrary to standard expectations, we find that thermally induced intraband particle-hole excitations can create and stabilize a uniform metallic phase with broken time-reversal symmetry as the temperature is "raised" in a region where the groundstate is a trivial metal.

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Wei Liu, Alexander Punnoose. 2015-04-30. Temperature-induced spontaneous time-reversal symmetry breaking on the honeycomb lattice. https://doi.org/10.1103/physrevlett.114.176402

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