Detail Project and Funding

Abstract: The proliferation of commercial laser systems is becoming an existential threat in many workplaces; current solutions against these threats are limited to fixed wavelength filters, and they are bulky and narrowband in their protection. Moreover, frequency agile lasers have the potential of defeating fixed filters, and broadband filters are severely plagued by low transmittance. This underscores the need for further research in novel technologies for eye and sensors protection. Our team is committed to realize a novel class of self-activating optical limiting and switching devices, with large angular acceptance and bandwidth, fast response and reset times and high laser damage threshold. To achieve such devices, we will research metallic and dielectric photonic resonators (thin-film multilayers) incorporating phase-change-materials (PCMs), namely vanadium oxide.

The project OPTIMIST aims at the following goals: build a dynamic model to analyse simultaneously optical and thermal effects in PCM-based photonic nanostructures; synthesize and characterize structures for the visible and infrared spectral regions; test the devices for eye and sensor protection.

The project OPTIMIST is financed by NATO Science for Peace and Security Programme.

The Scientific Results:
1) Second order nonlinear frequency generation at the nanoscale in dielectric platforms
2) Tunable second harmonic generation by an all-dielectric diffractive metasurface embedded in liquid crystals
3) Opto-thermal dynamics of thin-film optical limiters based on the VO2 phase transition
4) Optical tuning of dielectric nanoantennas for thermo-optically reconfigurable nonlinear metasurfaces