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arXiv · 2409.00502

Generalized BKT Transitions and Persistent Order on the Lattice

Evan Berkowitz·Seth Buesing·Shi Chen·Aleksey Cherman·Srimoyee Sen
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Abstract

The BKT transition in low-dimensional systems with a $U(1)$ global symmetry separates a gapless conformal phase from a trivially gapped, disordered phase, and is driven by vortex proliferation. Recent developments in modified Villain discretizations provide a class of lattice models which have a $\mathbb{Z}_W$ global symmetry that counts vortices mod W, mixed 't Hooft anomalies, and persistent order even at finite lattice spacing. While there is no fully-disordered phase (except in the original BKT limit $W=1$) there is still a phase boundary which separates gapped ordered phases from gapless phases. I'll describe a numerical Monte Carlo exploration of these phenomena.

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Evan Berkowitz, Seth Buesing, Shi Chen, Aleksey Cherman, Srimoyee Sen. 2024-08-31. Generalized BKT Transitions and Persistent Order on the Lattice. https://arxiv.org/abs/2409.00502

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