论文标题
液体和玻璃中的动力异质性来自中等顺序
Dynamical heterogeneities in liquid and glass originate from medium-range order
论文作者
论文摘要
在动态异质性或以相关，合作的方式重新排列的邻近颗粒处发生缓慢的松弛和塑性变形，例如金属玻璃和超冷液体。历史上通过四点，时间依赖性密度相关函数$χ_4（r，t）$描述了动态异质性。在本文中，我们认为$χ_4（r，t）$基本上包含与范霍夫相关函数$ g（r，t）$的中等订单相同的信息。换句话说，中等顺序是合作粒子运动的空间相关区域的起源。 Van Hove功能是描述动态异质性的首选工具，而不是四点函数，其物理含义较不透明。
Slow relaxation and plastic deformation in disordered materials such as metallic glasses and supercooled liquids occur at dynamical heterogeneities, or neighboring particles that rearrange in a correlated, cooperative manner. Dynamical heterogeneities have historically been described by a four-point, time-dependent density correlation function $χ_4 (r, t)$. In this paper, we posit that $χ_4 (r, t)$ contains essentially the same information about medium-range order as the Van Hove correlation function $G(r, t)$. In other words, medium-range order is the origin of spatially correlated regions of cooperative particle motion. The Van Hove function is the preferred tool for describing dynamical heterogeneities than the four-point function, for which the physical meaning is less transparent.
