论文标题
无序环境中的活动性布朗和惯性颗粒：均方位移的短时扩展
Active Brownian and inertial particles in disordered environments: short-time expansion of the mean-square displacement
论文作者
论文摘要
我们考虑一个活跃的棕色粒子在无序的二维能量或运动景观中移动。粒子的平均均方位数（MSD）在系统的短时扩展中进行分析计算。结果，对于过度引导的颗粒，自我塑性速度中的外部随机力场和无序均引起弹道行为，从而增加了具有急剧自我推向速度的活动粒子的弹道态度。力和运动景观中的空间相关性仅有助于MSD的立方和高阶功能。最后，对于惯性粒子，发现了两个超级巴利主义机制，其中MSD的缩放指数随时间为$α= 3 $，$α= 4 $。 我们通过计算机模拟确认我们的理论预测。此外，它们在随机环境中的自行胶体上进行了实验。
We consider an active Brownian particle moving in a disordered two-dimensional energy or motility landscape. The averaged mean-square-displacement (MSD) of the particle is calculated analytically within a systematic short-time expansion. As a result, for overdamped particles, both an external random force field and disorder in the self-propulsion speed induce ballistic behaviour adding to the ballistic regime of an active particle with sharp self-propulsion speed. Spatial correlations in the force and motility landscape contribute only to the cubic and higher order powers in time for the MSD. Finally, for inertial particles two superballistic regimes are found where the scaling exponent of the MSD with time is $α=3$ and $α=4$. We confirm our theoretical predictions by computer simulations. Moreover they are verifiable in experiments on self-propelled colloids in random environments.
