From Event: SPIE Nanoscience + Engineering, 2019
A system far from thermodynamic equilibrium is usually disordered yet ordered dissipative structures can still spontaneous form under certain conditions.1-2 The optical field provides a steady energy supply and enables a non-equilibrium dissipative state, where disorder-to-order transition occurs under anisotropic electrodynamic interactions. We find that a large number of Ag nanoparticles illuminated by a linearly polarized laser beam could self-assemble into partially ordered arrays, but they exhibited frequent structure transition between dimer chains and hexagonal nanoparticle lattices.3 In order to selective assembly of ordered lattice structures or dimer chains, a single Ag nanowire is illuminated to create a 3D interferometric optical field.4 The nanowire-guided self-assembly can be controlled by tuning the direction of linear polarization relative to the long-axis of a nanowire. The plasmonic nanowire can enhance the optical binding of nanoparticles both along and perpendicular to the laser polarization when the polarization is aligned at a specific angle. On the other hand, when specific dimer chains are perturbed and destabilized by another laser, their structures can self-heal after the perturbation is removed. Our observations suggest that light-driven self-organization of metal nanoparticles with strong optical binding interactions will provide new opportunities to discover new dissipative structures and build novel reconfigurable artificial nanostructures at mesoscale.
© (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Fan Nan and Zijie Yan, "Light-driven selective assembly and healing of optical matter (Conference Presentation)," Proc. SPIE 11083, Optical Trapping and Optical Micromanipulation XVI, 1108326 (Presented at SPIE Nanoscience + Engineering: August 15, 2019; Published: 9 September 2019); https://doi.org/10.1117/12.2529265.6083787170001.