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arXiv · 2412.19297

The XY model with vision cone: non-reciprocal vs. reciprocal interactions

Gabriele Bandini·Davide Venturelli·Sarah A. M. Loos·Asja Jelic·Andrea Gambassi
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Abstract

We study the behavior of the classical XY model on a two-dimensional square lattice, with interactions occurring within a vision cone of each spin. Via Monte Carlo simulations, we explore one non-reciprocal and two reciprocal implementations of these interactions. The corresponding energy involves couplings that depend non-trivially on the system's configuration, leading to both long-range and quasi-long-range ordered phases at low temperatures. Our results demonstrate that non-reciprocity is not essential for achieving long-range order at low temperatures. Using symmetry arguments, we provide a theoretical framework to explain these findings, and additionally we uncover an unexpected order-by-disorder transition.

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Gabriele Bandini, Davide Venturelli, Sarah A. M. Loos, Asja Jelic, Andrea Gambassi. 2024-12-26. The XY model with vision cone: non-reciprocal vs. reciprocal interactions. https://doi.org/10.1088/1742-5468%2Fadc243

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