Electron optics of nanoplasmonic metamaterials in bio/opto theranostics

Abstract

Opto-electronic coupling of plasmonic nano-antennas in the near infrared water window in vitro and in vivo is of growing interest for imaging contrast agents, spectroscopic labels and rulers, biosensing, drug-delivery, and optoplasmonic ablation. Metamaterials composed of nanoplasmonic meta-atoms offer improved figures of merit in many applications across a broader spectral window. Discrete and coupled dipole approximations effectively describe localized and coupled resonance modes in nanoplasmonic metamaterials. From numeric and experimental results have emerged four design principles to guide fabrication and implementation of metamaterials in bio-related devices and systems. Resonance intensity and sensitivity are enhanced by surface-to-mass of meta-atoms and lattice constant. Fano resonant coupling is dependent on meta-atom polarizability and lattice geometry. Internal reflection in plasmonic metaatom-containing polymer films enhances dissipation rate. Dimensions of self-assembled meta-atoms depend on balancing electrochemical and surface forces. Examples of these principles from our lab compare computation with images and spectra from ordered metal-ceramic and polymeric nanocomposite metamaterials for bio/opto theranostic applications. These principles speed design and description of new architectures for nanoplasmonic metamaterials that show promise for bioapplications.