- 2:45 PM

Robust Manufacturing of Novel Plasmonic Nanomaterials Via Liquid Phase Self Organization of Ultrathin Metal Films: Theory and Experiments

J. Trice, C. Favazza, D. G. Thomas, R. Kalyanaraman, and R. Sureshkumar. Washington University, Saint Louis, MO 63130

Light waves, when directed to the interface between a metal and a dielectric are capable of a resonant interaction with the mobile electrons present at the surface of the metal, giving rise to surface plasmons, i.e. density waves of electrons that propagate along the interface. Metallic nanoparticles on or embedded in dielectric materials offer great promise in “shepherding” light waves along nanoscale interconnects for ultrafast information processing. Similarly, such nanocomposites offer much potential in designing materials with enhanced light absorption. For instance, the optical response of a multi-metal nanocomposite material may be tailored to the solar spectrum via tuning volume fraction, particle size and/or shape. Laser-induced dewetting and self-organization in nanoscopic (1- 20 nm) metal films supported on dielectric substrates is a robust technique for the synthesis of optical/solar nanocomposites. Fluid phase instabilities, which arise as consequences of competing mechanisms including laser-film interactions, intermolecular forces, thermocapillary effects and Rayleigh breakup, initiate and foster the self-organization process [Appl. Phys. Lett., 91, 043105 (2007); Phys. Rev. B, 75, 235439 (2007); Nanotechnology, 17, 4229 (2006)] . The presentation will focus on experimental and theoretical studies (linear stability analysis and nonlinear dynamical simulations) that we have conducted recently to understand the nonlinear pathways of self-organization and its implications to manufacturing of optically active nanostructured materials. In particular, we will show that an intrinsic thermocapillary effect that arises from laser thermal transport in the film-substrate bilayer can greatly influence length scale selection in such systems.