Plasmon–Exciton Interactions Probed Using Spatial Coentrapment of Nanoparticles by Topological Singularities

We study plasmon–exciton interaction by using topological singularities to spatially confine, selectively deliver, cotrap and optically probe colloidal semiconductor and plasmonic nanoparticles. The interaction is monitored in a single quantum system in the bulk of a liquid crystal medium where nanoparticles are manipulated and nanoconfined far from dielectric interfaces using laser tweezers and topological configurations containing singularities. When quantum dot-in-a-rod particles are spatially colocated with a plasmonic gold nanoburst particle in a topological singularity core, its fluorescence increases because blinking is significantly suppressed and the radiative decay rate increases by nearly an order of magnitude owing to the Purcell effect. We argue that the blinking suppression is the result of the radiative rate change that mitigates Auger recombination and quantum dot ionization, consequently reducing nonradiative recombination. Our work demonstrates that topological singularities are an effective platform for studying and controlling plasmon–exciton interactions

Shape-Dependent Oriented Trapping and Scaffolding of Plasmonic Nanoparticles by Topological Defects for Self-Assembly of Colloidal Dimers in Liquid Crystals

We demonstrate scaffolding of plasmonic nanoparticles by topological defects induced by colloidal microspheres to match their surface boundary conditions with a uniform far-field alignment in a liquid crystal host. Displacing energetically costly liquid crystal regions of reduced order, anisotropic nanoparticles with concave or convex shapes not only stably localize in defects but also self-orient with respect to the microsphere surface. Using laser tweezers, we manipulate the ensuing nanoparticle-microsphere colloidal dimers, probing the strength of elastic binding and demonstrating self-assembly of hierarchical colloidal superstructures such as chains and arrays

Media 11: Optically generated reconfigurable photonic structures of elastic quasiparticles in frustrated cholesteric liquid crystals

Originally published in Optics Express on 26 March 2012 (oe-20-7-6870

Media 1: Optically generated reconfigurable photonic structures of elastic quasiparticles in frustrated cholesteric liquid crystals

Originally published in Optics Express on 26 March 2012 (oe-20-7-6870

Media 6: Optically generated reconfigurable photonic structures of elastic quasiparticles in frustrated cholesteric liquid crystals

Originally published in Optics Express on 26 March 2012 (oe-20-7-6870

Media 9: Optically generated reconfigurable photonic structures of elastic quasiparticles in frustrated cholesteric liquid crystals

Originally published in Optics Express on 26 March 2012 (oe-20-7-6870

Media 8: Optically generated reconfigurable photonic structures of elastic quasiparticles in frustrated cholesteric liquid crystals

Originally published in Optics Express on 26 March 2012 (oe-20-7-6870

Shape-Dependent Oriented Trapping and Scaffolding of Plasmonic Nanoparticles by Topological Defects for Self-Assembly of Colloidal Dimers in Liquid Crystals

We demonstrate scaffolding of plasmonic nanoparticles by topological defects induced by colloidal microspheres to match their surface boundary conditions with a uniform far-field alignment in a liquid crystal host. Displacing energetically costly liquid crystal regions of reduced order, anisotropic nanoparticles with concave or convex shapes not only stably localize in defects but also self-orient with respect to the microsphere surface. Using laser tweezers, we manipulate the ensuing nanoparticle-microsphere colloidal dimers, probing the strength of elastic binding and demonstrating self-assembly of hierarchical colloidal superstructures such as chains and arrays

Media 3: Optically generated reconfigurable photonic structures of elastic quasiparticles in frustrated cholesteric liquid crystals

Originally published in Optics Express on 26 March 2012 (oe-20-7-6870

Media 7: Optically generated reconfigurable photonic structures of elastic quasiparticles in frustrated cholesteric liquid crystals

Originally published in Optics Express on 26 March 2012 (oe-20-7-6870