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arXiv · 1205.1398

Non-Abelian gauge fields and topological insulators in shaken optical lattices

Abstract

Time-periodic driving like lattice shaking offers a low-demanding method to generate artificial gauge fields in optical lattices. We identify the relevant symmetries that have to be broken by the driving function for that purpose and demonstrate the power of this method by making concrete proposals for its application to two-dimensional lattice systems: We show how to tune frustration and how to create and control band touching points like Dirac cones in the shaken kagomé lattice. We propose the realization of a topological and a quantum spin Hall insulator in a shaken spin-dependent hexagonal lattice. We describe how strong artificial magnetic fields can be achieved for example in a square lattice by employing superlattice modulation. Finally, exemplified on a shaken spin-dependent square lattice, we develop a method to create strong non-Abelian gauge fields.

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Philipp Hauke, Olivier Tieleman, Alessio Celi, Christoph Ölschläger, Juliette Simonet, Julian Struck, Malte Weinberg, Patrick Windpassinger, Klaus Sengstock, Maciej Lewenstein, André Eckardt. 2012-08-01. Non-Abelian gauge fields and topological insulators in shaken optical lattices. https://doi.org/10.1103/physrevlett.109.145301

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