The optical properties of a concentric nanometer-sized spherical shell comprised of an (active) 3-level gain medium core and a surrounding plasmonic metal shell are investigated. Current research in optical metamaterials has demonstrated that including lossless plasmonic materials to achieve a negative permittivity in a nano-sized coated spherical particle can lead to novel optical properties such as resonant scattering as well as transparency or invisibility. However, in practice, plasmonic materials have high losses at optical frequencies. It will be demonstrated that a properly designed passive optical spherical core impregnated with a gain medium and coated with a concentric spherical plasmonic nano-shell will have a "super resonant" (SR) lasing state. The operating characteristics of this coated nano-particle (CNP) laser have been obtained numerically for a variety of configurations and will be reported here. Once the optical properties of the isolated active CNP inclusion are established, several examples of optical metamaterials using them as inclusions will be presented and analyzed. In particular, the effective material properties of these optical MTMs will be explored using effective medium theories that are applicable to a variety of inclusion configurations. Two-dimensional (2D) mono-layers of these active CNPs, which form metafilms; three-dimensional (3D) periodic arrays of these active CNPs; and 3D random distributions of these active CNPs will be described. The effective permittivities and refractive indexes of these optical MTMs will be compared and contrasted to those of their active CNP inclusions. In addition to the active MTMs, some examples of nano-photonic applications enabled by the unique properties of these inclusions will also be presented. Specifically metamaterial pigments derived from exploiting the high absorption and low scattering properties of the passive CNP particle will be explored for possible use in color display technology as well as the use of the SR lasing state and localized plasmon resonance of the active CNP for nano-sensing applications.

The human body is dynamic and understanding such complexity for accurate diagnostics and therapies remains a challenge due to lack of minimally-invasive biotechnologies capable of long-term measurements of various biochemical and bioelectrical signals simultaneously from single cells to cell networks. Biocompatibility is a major challenge but recent advancements in micro- and nano-fabrication has shown that patterned protruding pillars from surfaces at the micro- and nano-scale can mimic intrinsic biological structural cues to trigger strong cell adhesion, engulfment, and growth, providing a means by which to engineer the biocompatibility for controlled cell-device bio-interfaces. Here, we sought to leverage the unique biocompatibility of engineered three-dimensional (3D) features with integrated biochemical and bioelectrical sensor arrays to create a multi-modal platform for complex systems biological research. For the biochemical sensor, we introduced a tunable optical nanoantenna that is driven wirelessly by incident laser light (photons) to create a highly localized electric field capable of enhancing the photon scattering rate of nearby chemical bonds, a unique signature that provides a means to fingerprint the local biomolecular ensembles depending on the color of detected scattered photons. By a novel scalable fabrication technique, we merged such nano-sensors with 3D micropillar electrode arrays to create a device with hybrid biophotonic and bioelectronic functionality. We revealed the unique optical properties by micro-reflectance measurements and numerical simulations and verified by spectroscopic measurements a million-fold enhancement to the scattered photon signature from a standard chemical monolayer. We showed favorable bioelectrical properties by electrochemical impedance spectroscopy and cyclic voltammetry, revealing a stable electrochemical interface and reduced resistance due to 3D geometry enabling improved transduction of electrical signals, useful for higher signal to noise ratios in bioelectrical measurements. Overall, we demonstrated the scalable fabrication and unique optical and electrical properties suitable for next generation multi-modal bio-interfacing platforms. / This work was supported by US AFOSR Young Investigator Award FA9550-18-1-0328, US AFOSR DURIP Award FA9550-19-1-0287, US NIST grant 70NANB18H201, and US NIST grant 70NANB19H163. / Master of Science / The human body is dynamic and understanding such complexity for accurate diagnostics and therapies remains a challenge due to lack of minimally-invasive biotechnologies capable of long-term measurements of various biochemical and bioelectrical signals simultaneously from single cells to cell networks. Biocompatibility is a major challenge but recent advancements in micro- and nano-fabrication has shown that patterned protruding pillars from surfaces at the micro- and nano-scale can mimic intrinsic biological structural cues to trigger strong cell adhesion, engulfment, and growth, providing a means by which to engineer the biocompatibility for controlled cell-device bio-interfaces. Here, we sought to leverage the unique biocompatibility of engineered three-dimensional (3D) features with integrated biochemical and bioelectrical sensor arrays to create a multi-modal platform for complex systems biological research. For the biochemical sensor, we introduced a tunable optical nanoantenna that is driven wirelessly by incident laser light (photons) to create a highly localized electric field capable of enhancing the photon scattering rate of nearby chemical bonds, a unique signature that provides a means to fingerprint the local biomolecular ensembles depending on the color of detected scattered photons. By a novel scalable fabrication technique, we merged such nano-sensors with 3D micropillar electrode arrays to create a device with hybrid biophotonic and bioelectronic functionality. We revealed the unique optical properties by micro-reflectance measurements and numerical simulations and verified by spectroscopic measurements a million-fold enhancement to the scattered photon signature from a standard chemical monolayer. We showed favorable bioelectrical properties by electrochemical impedance spectroscopy and cyclic voltammetry, revealing a stable electrochemical interface and reduced resistance due to 3D geometry enabling improved transduction of electrical signals, useful for higher signal to noise ratios in bioelectrical measurements. Overall, we demonstrated the scalable fabrication and unique optical and electrical properties suitable for next generation multi-modal bio-interfacing platforms.