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arXiv · 1502.03432

Practical new platform for interaction-enabled topological phases

Ching-Kai Chiu·D. I. Pikulin·M. Franz
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Abstract

Systems of strongly interacting particles, fermions or bosons, can give rise to topological phases that are not acessible to non-interacting systems. Many such interaction-enabled topological phases have been discussed theoretically but few experimental realizations exists. Here we propose a new platform for interacting topological phases of fermions with time reversal symmetry $\bar T$ (such that $\bar T^2=1$) that can be realized in vortex lattices in the surface state of a topological insulator. The constituent particles are Majorana fermions bound to vortices and antivortices of such a lattice. We explain how the $\bar T$ symmetry arises and discuss ways in which interactions can be experimentally tuned and detected. We show how these features can be exploited to realize a class of interaction-enabled crystalline topological phases that have no analog in weakly interacting systems.

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Ching-Kai Chiu, D. I. Pikulin, M. Franz. 2015-12-10. Practical new platform for interaction-enabled topological phases. https://doi.org/10.1103/physrevb.92.241115

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