We design a nematic collider for controlled out-of-equilibrium anisotropic aggregation of spherical colloidal particles. The nematic surrounding imparts dipolar interactions among the spheres. A bidirectional backflow of the nematic liquid crystal in a periodic electric field forces the spheres to collide with each other. The inelastic collisions are of two types, head to tail and head to head. Head-to-tail collisions of dipoles result in longitudinal aggregation while head-to-head collisions promote aggregation in the transversal direction. The frequency of head-to-head collisions is set by the impact parameter that controls the resulting shape of aggregates, their anisotropy, and fractal dimension.
Physical Review Letters
Copyright 2011 American Physical Society. Available on publisher's site at http://dx.doi.org/10.1103/PhysRevLett.106.047801.
Pishnyak, Oleg P.; Shiyanovskii, Sergij V.; Lavrentovich, Oleg (2011). Inelastic Collisions and Anisotropic Aggregation of Particles in a Nematic Collider Driven by Backflow. Physical Review Letters 106(4) doi: 10.1103/PhysRevLett.106.047801. Retrieved from https://oaks.kent.edu/cpippubs/214