论文标题
活性流体相分离的经典成核理论
Classical Nucleation Theory for Active Fluid Phase Separation
论文作者
论文摘要
经典成核理论（CNT）将稀有成核事件与生长核的自由能景观联系起来，是理解被动流体中相变动力学的核心。非平衡系统中的成核很难描述，因为没有自由能，而是基于动态依赖性的准电位，通常必须从数值上找到。在这里，我们将CNT扩展到由最小的场理论模型（主动模型B+）控制的一类活动相分离系统。在CNT假设的小噪声和过饱和限制中，我们通过分析用于液体蒸气相分离的准势率及其成核屏障。至关重要的是，对于我们的结果，详细的平衡虽然在显微镜下被活性损坏，但沿激体轨迹恢复，在CNT中，核半径涉及核半径作为唯一的反应坐标。
Classical nucleation theory (CNT), linking rare nucleation events to the free energy landscape of a growing nucleus, is central to understanding phase-change kinetics in passive fluids. Nucleation in non-equilibrium systems is much harder to describe because there is no free energy, but instead a dynamics-dependent quasi-potential that typically must be found numerically. Here we extend CNT to a class of active phase separating systems governed by a minimal field-theoretic model (Active Model B+). In the small noise and supersaturation limits that CNT assumes, we compute analytically the quasi-potential, and hence nucleation barrier, for liquid-vapor phase separation. Crucially to our results, detailed balance, although broken microscopically by activity, is restored along the instanton trajectory, which in CNT involves the nuclear radius as the sole reaction coordinate.
