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arXiv · 2405.20266

Hyperuniformity in Ashkin-Teller model

Indranil Mukherjee·P. K. Mohanty
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Abstract

We show that equilibrium systems in $d$ dimension that obey the inequality $dν> 2,$ known as Harris criterion, exhibit suppressed energy fluctuation in their critical state. Ashkin-Teller model is an example in $d=2$ where the correlation length exponent $ν$ varies continuously with the inter-spin interaction strength $λ$ and exceeds the value $\frac d2$ set by Harris criterion when $λ$ is negative; there, the variance of the subsystem energy across a length scale $l$ varies as $l^{d-α}$ with hyperuniformity exponent $α= 2(1-ν^{-1}).$ Point configurations constructed by assigning unity to the sites which has coarse-grained energy beyond a threshold value also exhibit suppressed number fluctuation and hyperuniformiyty with same exponent $α.$

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Indranil Mukherjee, P. K. Mohanty. 2024-09-12. Hyperuniformity in Ashkin-Teller model. https://doi.org/10.1088/1361-648x%2Fad6c99

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