$\mathbb{Z}_2$ topological insulator analog for vortices in an interacting bosonic quantum fluid

O. Bleu; G. Malpuech; D. D. Solnyshkov

doi:10.1038/s41467-018-06520-7

paper

$Z_{2}$ topological insulator analog for vortices in an interacting bosonic quantum fluid

arXiv:1709.01830 · doi:10.1038/s41467-018-06520-7

Abstract

$Z_{2}$ topological insulators for photons and in general bosons cannot be strictly implemented because of the lack of symmetry-protected pseudospins. We show that the required protection can be provided by the real-space topological excitation of an interacting quantum fluid: quantum vortex. We consider a Bose-Einstein Condensate at the $Γ$ point of the Brillouin zone of a quantum valley Hall system based on two staggered honeycomb lattices. We demonstrate the existence of a coupling between the winding number of a vortex and the valley of the bulk Bloch band. This leads to chiral vortex propagation at the zigzag interface between two regions of inverted staggering, where the winding-valley coupling provides true topological protection against backscattering, contrary to the interface states of the non-interacting Hamiltonian. This configuration is an analog of a $Z_{2}$ topological insulator for quantum vortices.

$Z_{2}$ topological insulator analog for vortices in an interacting bosonic quantum fluid

Abstract

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Cited by in corpus (24)

Z2​ topological insulator analog for vortices in an interacting bosonic quantum fluid

Abstract

References in corpus (14)

Cited by in corpus (24)

$Z_{2}$ topological insulator analog for vortices in an interacting bosonic quantum fluid