Optimal design of nanoplasmonic materials using genetic algorithms as a multi-parameter optimization tool

摘要

An optimal control approach based on multiple parameter genetic algorithms isapplied to the design of plasmonic nanoconstructs with pre-determined opticalproperties and functionalities. We first develop nanoscale metallic lenses thatfocus an incident plane wave onto a pre-specified, spatially confined spot. Ourresults illustrate the role of symmetry breaking and unravel the principlesthat favor dimeric constructs for optimal light localization. Next we design aperiodic array of silver particles to modify the polarization of an incident,linearly-polarized plane wave in a desired fashion while localizing the lightin space. The results provide insight into the structural features thatdetermine the birefringence properties of metal nanoparticles and their arrays.Of the variety of potential applications that may be envisioned, we note thedesign of nanoscale light sources with controllable coherence and polarizationproperties that could serve for coherent control of molecular or electronicdynamics in the nanoscale.