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arXiv · 0909.5161

Topological phase transitions in the non-Abelian honeycomb lattice

A. Bermudez·N. Goldman·A. Kubasiak·M. Lewenstein·M. A. Martin-Delgado
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Abstract

Ultracold Fermi gases trapped in honeycomb optical lattices provide an intriguing scenario, where relativistic quantum electrodynamics can be tested. Here, we generalize this system to non-Abelian quantum electrodynamics, where massless Dirac fermions interact with effective non-Abelian gauge fields. We show how in this setup a variety of topological phase transitions occur, which arise due to massless fermion pair production events, as well as pair annihilation events of two kinds: spontaneous and strongly-interacting induced. Moreover, such phase transitions can be controlled and characterized in optical lattice experiments.

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A. Bermudez, N. Goldman, A. Kubasiak, M. Lewenstein, M. A. Martin-Delgado. 2010-03-25. Topological phase transitions in the non-Abelian honeycomb lattice. https://doi.org/10.1088/1367-2630%2F12%2F3%2F033041

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