Gain-assisted plasmonic metamaterials: mimicking nature to go across scales

Nature as a source of inspiration for designing and fabricating nanostructured materials with unconventional properties is an unparalleled driving force of this work leading to low-loss metamaterials. Here, we report about a multipronged approach to create optical metamaterials based on plasmonic nanostructures, hierarchical organization and interplay between plasmon elements and excitonic molecules. This work is focused on strategies and approaches to produce gain to metamaterials across scales with the aim of realizing low-loss optical materials and unlocking their unconvetional electromagnetic properties. Finally, we describe how a biomimetic approach based on gain-functionalized bionanoparticle can be harnessed for diagnostics and theranostics.