Z2 Topological insulator of ultra cold atoms in bichromatic optical lattices

Ahad K. Ardabili; Tekin Dereli; Özgür E. Müstecaplıoğlu

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arXiv · 1302.5524

Z2 Topological insulator of ultra cold atoms in bichromatic optical lattices

Ahad K. Ardabili·Tekin Dereli·Özgür E. Müstecaplıoğlu

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Abstract

We investigate the effect of a strong bichromatic deformation to the $\mathbb{Z}_{2}$ topological insulator in a fermionic ultracold atomic system proposed by B. B\'eri and N. R. Cooper, Phys.Rev.Lett. {\bf 107}, 145301 (2011). Large insulating gap of this system allows for examination of strong perturbations. We consider bichromatic perturbation along all axes on a triangular optical lattice. We find that $\mathbb{Z}_{2}$ topological character of the system is robust up to a certain depth of the deformation. The lowest band can become topologically trivial while the lowest two bands are always protected.

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Ahad K. Ardabili, Tekin Dereli, Özgür E. Müstecaplıoğlu. 2013-02-22. Z2 Topological insulator of ultra cold atoms in bichromatic optical lattices. https://arxiv.org/abs/1302.5524

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