Galliano Leonardo, Cates Michael E, Berthier Ludovic
Laboratoire Charles Coulomb (L2C), Université de Montpellier, CNRS, 34095 Montpellier, France.
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, United Kingdom.
Phys Rev Lett. 2023 Jul 28;131(4):047101. doi: 10.1103/PhysRevLett.131.047101.
When driven by nonequilibrium fluctuations, particle systems may display phase transitions and physical behavior with no equilibrium counterpart. We study a two-dimensional particle model initially proposed to describe driven non-Brownian suspensions undergoing nonequilibrium absorbing phase transitions. We show that when the transition occurs at large density, the dynamics produces long-range crystalline order. In the ordered phase, long-range translational order is observed because equipartition of energy is lacking, phonons are suppressed, and density fluctuations are hyperuniform. Our study offers an explicit microscopic model where nonequilibrium violations of the Mermin-Wagner theorem stabilize crystalline order in two dimensions.
当由非平衡涨落驱动时，粒子系统可能会展现出相变以及不存在平衡对应物的物理行为。我们研究了一个二维粒子模型，该模型最初是为描述经历非平衡吸收相变的驱动非布朗悬浮液而提出的。我们表明，当相变在高密度下发生时，动力学产生长程晶体序。在有序相中，观察到长程平移序，这是因为缺乏能量均分，声子被抑制，且密度涨落是超均匀的。我们的研究提供了一个明确的微观模型，其中对默明 - 瓦格纳定理的非平衡违背在二维中稳定了晶体序。
