SHAPING THE OPTICAL AND THERMAL PROPERTIES OF PLASMONIC NANOSTRUCTURES FOR BIOLOGICAL APPLICATIONS

Metallic nanostructures supporting localized surface plasmon resonances have the potential to both generate intense local optical fields and act as efficient nano heat sources, opening up to plenty of new science and applications in areas ranging from integrated optics to biomedicine. In this contribution, we discuss the specific engineering of both optical and thermal properties of resonant plasmonic nanosystems and detail some of their respective biological applications that have been developed within the group. In a first part, we will focus on the control of the subwavelength optical confinement in different configurations of electromagnetically coupled metal nanostructures. Special attention is paid to gap antennas formed by two adjacent gold nanorods separated by a subwavelength dielectric gap. We discuss the use of two-photon induced luminescence (TPL) micro-spectroscopy as an efficient tip less method to probe the actual electromagnetic mode distribution along the structures and monitor its evolution with the illumination wavelength. Our experimental data are very well corroborated by 3D numerical simulations [1]. The efficient concentration of light fields down to the nanoscale volumes is particularly attractive for applications involving the interaction of photons with very small amounts o