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arXiv · 2107.11656

Phase diagram of 1+1D Abelian-Higgs model and its critical point

Titas Chanda·Maciej Lewenstein·Jakub Zakrzewski·Luca Tagliacozzo
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Abstract

We determine the phase diagram of the Abelian-Higgs model in one spatial dimension and time (1+1D) on a lattice. We identify a line of first order phase transitions separating the Higgs region from the confined one. This line terminates in a quantum critical point above which the two regions are connected by a smooth crossover. We analyze the critical point and find compelling evidences for its description as the product of two non-interacting systems, a massless free fermion and a massless free boson. However, we find also some surprizing results that cannot be explained by our simple picture, suggesting this newly discovered critical point to be an unusual one.

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Titas Chanda, Maciej Lewenstein, Jakub Zakrzewski, Luca Tagliacozzo. 2022-02-13. Phase diagram of 1+1D Abelian-Higgs model and its critical point. https://doi.org/10.1103/physrevlett.128.090601

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