Light-Driven Self-Organization of Plasmonic Nanoparticles into Artificial Materials

The ability to reconfigure nanoscale building blocks into different architectures, as if they were Lego pieces, has enormous potential for nanotechnology. The development of colloidal synthesis has largely increased the availability of nanoparticles with well-controlled sizes and shapes. Bottom-up assembly of these nanoscale building blocks opens the prospect of creating novel artificial materials with unusual properties. However, it is still a great challenge to achieve precise, controlled, and reconfigurable assembly of nanoparticles. In this talk, I will show how we are using light to address this fundamental challenge in nanotechnology. We are exploring optical trapping and optical binding interactions to create artificial nanomaterials. Shaped optical fields are created by modulating the intensity, phase, and polarization of laser beams in space and time. Self-organization arises from interparticle electrodynamic interactions among strongly scattering plasmonic nanoparticles, leading to a new type of material: reconfigurable optical matter with discrete nanoparticle superlattices. New science has emerged in these artificial materials, for example, optical torque reversal, self-replication and self-healing. The developed optical methods will lead to more research opportunities and applications in microfluidics, optomechanics, microrheology, and cell biology.