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arXiv · 2404.17504

Phase diagram of generalized XY model using tensor renormalization group

Abhishek Samlodia·Vamika Longia·Raghav G. Jha·Anosh Joseph
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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 (BKT) and Ising class. We explore the model for a wide range of temperatures, $T$, and the deformation parameter, $\Delta$, and compute specific heat along with integer and half-integer magnetic susceptibility, finding both BKT-like and Ising-like transitions and the region where they meet.

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Abhishek Samlodia, Vamika Longia, Raghav G. Jha, Anosh Joseph. 2024-04-26. Phase diagram of generalized XY model using tensor renormalization group. https://doi.org/10.1103/physrevd.110.034504

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