In this work we use computer simulation to investigate systems of non-spherical nanoparticles in nematic liquid crystals (NLCs). We aim at understanding the behavior of these nanoscale systems, in order to explore potential applications in photonics, optical sensors and electro-optical nanoswitches. Most of the previous work in this topic has focused on spherical particles in NLCs. The particles' inclusion distorts the NLC, which form defect structures around the particles that give rise to strong interparticle interactions (up to several thousands of kT for micron-sized spherical particles). These strong interactions can be used to bind the particles together and assemble them into ordered structures [1-4]. We report results for the potentials of mean force and the defect structures that arise when non-spherical nanoparticles are immersed in a NLC. Using a mesoscale theory in terms of the tensor order parameter Q of the NLC, we analyze several systems of nanoparticles with different shapes (e.g., spherocylindrical, cubic, other faceted polyhedra), and we compare with similar results for spherical particles of comparable sizes. Our results [5] indicate that the NLC forms defect structures consisting of distorted Saturn rings around the non-spherical nanoparticles. Strong interactions arise between these particles, in analogy to those observed for their spherical counterparts. However, the non-spherical nanoparticles also tend to adopt preferred orientations relative to the NLC director field n(r), which causes the interparticle interactions to be highly directional and anisotropic. As a result, the nanoparticles can be assembled into ordered structures different from the close-packed arrays formed by spherical particles.

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