Nanoplasmonics and Metamaterials have in the last 15 years inspired scientists to think about photonics beyond traditional constraints imposed by natural materials in which light propagates to conceive functionalities such as subwavelength imaging and broadband ultraslow light. While most concepts have initially been demonstrated at longer wavelengths and for microwaves, they have continuously moved to optical frequencies and beyond. Embracing nonlinearity and (quantum) gain , exciting phenomena such as ‘dark-light’  and cavity-free  nano-lasing and room temperature single molecule strong coupling  have been unveiled.
In the talk I shall illuminate new horizons for active nanophotonics and topological metamaterials with quantum gain on the nanoscale, discussing recently demonstrated room-temperature strong coupling of single molecules in a plasmonic nano-cavity  and near-field strong coupling of single quantum dots . I will further discuss how the ‘trapped-rainbow’ principle  has been a trail-blazer for ultra-slow waves on the nanoscale  with innovative applications such as cavity-free stopped-light nanolasing . Finally, I will offer an outlook on how quantum nanophotonics, topological (quantum-) metamaterials and quantum chaos  are enabling ultrafast nano-lasers, semiconductor metamaterials, controlled nano-chemistry and phonon lasing with applications in quantum science and nano-technology, semiconductor optoelectronics, photonic energy and photovoltaics as well as for bio-sensing and materials chemistry on the nanoscale.
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