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arXiv · 2106.15823

Phase diagram of an extended parafermion chain

Jurriaan Wouters·Fabian Hassler·Hosho Katsura·Dirk Schuricht
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Abstract

We study the phase diagram of an extended parafermion chain, which, in addition to terms coupling parafermions on neighbouring sites, also possesses terms involving four sites. Via a Fradkin--Kadanoff transformation the parafermion chain is shown to be equivalent to the non-chiral $\mathbb{Z}_3$ axial next-nearest neighbour Potts model. We discuss a possible experimental realisation using hetero-nanostructures. The phase diagram contains several gapped phases, including a topological phase where the system possesses three (nearly) degenerate ground states, and a gapless Luttinger-liquid phase.

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Jurriaan Wouters, Fabian Hassler, Hosho Katsura, Dirk Schuricht. 2021-06-30. Phase diagram of an extended parafermion chain. https://doi.org/10.21468/scipostphyscore.5.1.008

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