Long-range Order and Directional Defect Propagation in the Nonreciprocal XY Model with Vision Cone Interactions

Sarah A. M. Loos; Sabine H. L. Klapp; Thomas Martynec

doi:10.1103/physrevlett.130.198301

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arXiv · 2206.10519

Long-range Order and Directional Defect Propagation in the Nonreciprocal XY Model with Vision Cone Interactions

Sarah A. M. Loos·Sabine H. L. Klapp·Thomas Martynec

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Abstract

We study a two-dimensional, nonreciprocal XY model, where each spin interacts only with its nearest neighbours in a certain angle around its current orientation, i.e., its `vision cone'. Using energetic arguments and Monte-Carlo simulations we show that a true long-range ordered phase emerges. A necessary ingredient is a configuration-dependent bond dilution entailed by the vision cones. Strikingly, defects propagate in a directional manner, thereby breaking the parity and time-reversal symmetry of the spin dynamics. This is detectable by a non-zero entropy production rate.

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Sarah A. M. Loos, Sabine H. L. Klapp, Thomas Martynec. 2022-12-01. Long-range Order and Directional Defect Propagation in the Nonreciprocal XY Model with Vision Cone Interactions. https://doi.org/10.1103/physrevlett.130.198301

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