By performing dynamic Monte Carlo simulations, we investigate the microrheology of isotropic suspensions of hard-core colloidal cuboids. In particular, we infer the local viscoelastic behavior of these fluids by studying the dynamics of a probe spherical particle that is incorporated in the host phase and is dragged by an external force. This technique, known as active microrheology, allows one to characterize the microscopic response of soft materials upon application of a constant force, whose intensity spans here three orders of magnitude. By tuning the geometry of cuboids from oblate to prolate as well as the system density, we observe different responses that are quantified by measuring the effective friction perceived by the probe particle. The resulting friction coefficient exhibits a linear regime at forces that are much weaker and larger than the thermal forces, whereas a nonlinear, force-thinning regime is observed at intermediate force intensities.

中文翻译：

---

硬长方体胶体悬浮液的活性微流变学

通过执行动态蒙特卡罗模拟，我们研究了硬核胶体长方体的各向同性悬浮液的微观流变学。特别是，我们通过研究包含在主体相中并被外力拖动的探针球形粒子的动力学来推断这些流体的局部粘弹性行为。这种称为主动微流变学的技术允许人们在施加恒定力时表征软材料的微观响应，其强度在这里跨越三个数量级。通过调整从扁长方体到扁长方体的几何形状以及系统密度，我们观察到通过测量探针粒子感知的有效摩擦来量化的不同响应。