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arXiv · 2608.29343

"Ultra-weak" First-Order Phase Transition in Biaxial Liquid Crystals

Soumyajit Pramanick·Mrinal Kanti Debnath·Nababrata Ghoshal·Soumen Kumar Roy·Sudeshna Dasgupta
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Abstract

We report high-resolution Monte Carlo evidence characterizing the hierarchy of transition strengths in biaxial nematogens. By employing multiple histogram reweighting on large lattices, we demonstrate that while the isotropic-to-uniaxial ($I \to N_U$) transition is symmetry-enforced first-order, the uniaxial-to-biaxial ($N_U \to N_B$) transition in the region between the tricritical point and the triple point ($\lambda = 0.26$) is proximity-driven and more than an order of magnitude smaller for large system sizes. Such a class of ultra-weak first-order transitions could be a new pathway for future investigations.

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Soumyajit Pramanick, Mrinal Kanti Debnath, Nababrata Ghoshal, Soumen Kumar Roy, Sudeshna Dasgupta. 2026-08-29. "Ultra-weak" First-Order Phase Transition in Biaxial Liquid Crystals. https://arxiv.org/abs/2608.29343

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