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arXiv · 1611.00796

Topological Quantum Liquids with Long-Range Couplings

Kristian Patrick·Titus Neupert·Jiannis K. Pachos
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Abstract

Very few topological systems with long-range couplings have been considered so far due to our lack of analytic approaches. Here we extend the Kitaev chain, a 1D quantum liquid, to infinite-range couplings and study its topological properties. We demonstrate that, even though topological phases are intimately linked to the notion of locality, the infinite-range couplings give rise to topological zero and non-zero energy Majorana end modes depending on the boundary conditions of the system. We show that the analytically derived properties are to a large degree stable against modifications to decaying long-range couplings. Our work opens new frontiers for topological states of matter that are relevant to current experiments where suitable interactions can be designed.

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Kristian Patrick, Titus Neupert, Jiannis K. Pachos. 2020-08-25. Topological Quantum Liquids with Long-Range Couplings. https://doi.org/10.1103/physrevlett.118.267002

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