Introduction to Physics and technology of light at the nanoscale The thematic area of physics and technologies of light at the nanoscale investigates phenomena that characterize the interaction of electromagnetic radiation with nanostructured materials. This field encompasses research activities aimed at the realization of innovative inorganic and organic nanomaterials (2-dimensional materials, nanowires, metasurfaces, and nanofibers), the experimental study and modelling of the optical properties of the obtained nanostructures, and the design and realization of photonic and optoelectronic devices, such as continuous wave (cw) and pulsed coherent light sources, photodetectors, optomechanical components, and 3-dimensional (3D) waveguides. The synthesis and fabrication of elongated nanostructures with high aspect ratio provides a novel class of materials with anisotropic optical properties and the capability of guiding and transporting light at various length scales. Recently, InP-InAs-InP multi-shell NWs were fabricated with emission at multi-wavelengths, attributed to different quantum emitters realized in individual nanowires. Semiconductor nanowires are interesting also for their collective optical properties, as the polarized reflectance of random assemblies of vertical nanowires, which shows well-defined modulation of the intensity by varying the angle of incidence. In addition, polymer nanofibers were reported as flexible elongated nanostructures capable of long-distance transport of the light generated by the nanoscale light sources incorporated in them. Nanofibers can be also assembled in complex nanopho-
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Activity Report 2020