Activity-Enhanced Ordering in Fluctuation-Induced First-Order Transitions

Suvendra K. Sahoo

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arXiv · 2605.30887

Activity-Enhanced Ordering in Fluctuation-Induced First-Order Transitions

Suvendra K. Sahoo

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Abstract

Fluctuations can drive otherwise continuous phase transitions to first order through the Brazovskii mechanism. We study how these fluctuation-induced transitions are modified in active systems by introducing nonequilibrium spatiotemporally correlated noise. We show that, while the transition remains fluctuation-induced first order, activity systematically suppresses these fluctuation effects, shifting the transition to higher temperatures and rendering it increasingly weakly first order. As a result, ordering is enhanced without inducing a spinodal instability of the isotropic phase, as confirmed by direct numerical simulations. In the strong-activity limit, fluctuation effects disappear and mean-field behavior is recovered. Our results identify activity as a generic control parameter for tuning the strength of fluctuation-induced first-order transitions.

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BibTeX RIS

Suvendra K. Sahoo. 2026-05-29. Activity-Enhanced Ordering in Fluctuation-Induced First-Order Transitions. https://arxiv.org/abs/2605.30887

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