Phase diagram of generalized XY model using the tensor renormalization group

Samlodia, Abhishek (ORCID:0000000348021356); Longia, Vamika (ORCID:0009000425422805); Jha, Raghav G. (ORCID:0000000329330102); Joseph, Anosh (ORCID:0000000342888207)

doi:10.1103/physrevd.110.034504

DOE OSTI · 2427028

Phase diagram of generalized XY model using the tensor renormalization group

Samlodia, Abhishek (ORCID:0000000348021356)·Longia, Vamika (ORCID:0009000425422805)·Jha, Raghav G. (ORCID:0000000329330102)·Joseph, Anosh (ORCID:0000000342888207)

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Abstract

We use the higher-order tensor renormalization group method to study the two-dimensional generalized XY model that admits integer and half-integer vortices. This model is the deformation of the classical XY model and has a rich phase structure consisting of nematic, ferromagnetic, and disordered phases and three transition lines belonging to the Berezinskii-Kosterlitz-Thouless and Ising class. We explore the model for a wide range of temperatures, T , and the deformation parameter, Δ , and compute specific heat along with integer and half-integer magnetic susceptibility, finding both Berezinskii-Kosterlitz-Thouless-like and Ising-like transitions and the region where they meet. Published by the American Physical Society 2024

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2-dimensional systems 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS BKT transition Classical statistical mechanics Phase transitions Renormalization group XY model

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Samlodia, Abhishek (ORCID:0000000348021356), Longia, Vamika (ORCID:0009000425422805), Jha, Raghav G. (ORCID:0000000329330102), Joseph, Anosh (ORCID:0000000342888207). 2024-08-06. Phase diagram of generalized XY model using the tensor renormalization group. https://doi.org/10.1103/physrevd.110.034504

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