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arXiv · 2207.08840

Chiral Spin-Chain Interfaces Exhibiting Event-Horizon Physics

Matthew D. Horner·Andrew Hallam·Jiannis K. Pachos
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Abstract

The interface between different quantum phases of matter can give rise to novel physics, such as exotic topological phases or non-unitary conformal field theories. Here we investigate the interface between two spin chains in different chiral phases. Surprisingly, the mean-field theory description of this interacting composite system is given in terms of Dirac fermions in a curved space-time geometry. In particular, the boundary between the two phases represents a black hole horizon. We demonstrate that this representation is faithful both analytically, by employing bosonisation to obtain a Luttinger liquid model, and numerically, by employing Matrix Product State methods. A striking prediction from the black hole equivalence emerges when a quench, at one side of the interface between two opposite chiralities, causes the other side to thermalise with the Hawking temperature for a wide range of parameters and initial conditions.

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Matthew D. Horner, Andrew Hallam, Jiannis K. Pachos. 2022-07-18. Chiral Spin-Chain Interfaces Exhibiting Event-Horizon Physics. https://doi.org/10.1103/physrevlett.130.016701

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