We experimentally characterize heterogeneous nonexponential relaxation in bidisperse supercooled colloidal liquids utilizing a recent concept called “softness” [Phys. Rev. Lett.114, 108001 (2015)]. Particle trajectory and structure data enable classification of particles into subgroups with different local environments and propensities to hop. We determine residence times

between particle hops and show that

derived from particles in the same softness subgroup are exponentially distributed. Using the mean residence time

for each softness subgroup, and a Kramers’ reaction rate model, we estimate the activation energy barriers

for particle hops, and show that both

and

are monotonic functions of softness. Finally, we derive information about the combinations of large and small particle neighbors that determine particle softness, and we explicitly show that multiple exponential relaxation channels in the supercooled liquid give rise to its nonexponential behavior.

我们利用称为“柔软性”的最新概念，通过实验表征了双分散过冷胶体液体中的非均质非指数松弛。莱特牧师 114，108001（2015）]。粒子轨迹和结构数据可将粒子分类为具有不同局部环境和跳跃倾向的子组。我们确定停留时间

在粒子跳之间显示

从相同柔软度子集中的粒子派生的指数分布。使用平均停留时间

对于每个柔软度亚组和Kramers反应速率模型，我们估计了活化能垒

对于粒子跳，并表明两者

和

是柔软度的单调函数。最后，我们得出有关决定颗粒柔软度的大颗粒邻居和小颗粒邻居的组合的信息，并且我们明确表明，过冷液体中的多个指数弛豫通道会引起其非指数行为。