EUROPHOTON 2022

We report on the recent progress in solid-state lasers emitting ultrashort pulses around 2 µm based on broadband-emitting gain media: disordered crystals (garnets and aluminates) and “mixed” transparent ceramics (sesquioxides) doped with Tm3+ and Tm3+/Ho3+ ions. The role of multiphonon-assisted long-wave emissions in reaching sub-50 fs pulse durations is discussed.

We demonstrate a silicon nitride waveguide-based optical parametric oscillator exploiting four-wave mixing (FWM), synchronously fiber-laser pumped at 40 MHz repetition rate and showing an idler tunability across 95 nm near 1150 nm with a output pulse energy up to 63 pJ and a bandwidth of about 10 nm.

A waveguide-based OPO (WOPO) exploiting four-wave mixing in the emerging tantalum pentoxide platform is investigated. The WOPO, pumped with 500 fs long pulses centered at 1.55 $\mu$m wavelength with 2 nJ energy, provided up to 6 pJ pulse energy at 1.46 $\mu$m wavelength. It shows potential to be fully integrated on a chip.

We demonstrate simple and efficient broadband mid-infrared generation via optical parametric amplification driven inside a dispersion-engineered nanophotonic waveguide. Using a commercially-available pulsed pump laser centered at 1045 nm and a CW telecom seed, we achieve up to 60% of conversion efficiency and 140 nm of mid-infrared spectral bandwidth.

We report on our recent developments on rare-earth-based gain and lasing directly on silicon photonic chips. We demonstrate laser emission around 1.8-1.9 $\mu$m in thulium-doped tellurium oxide coated silicon hybrid microdisks, with on-chip output powers of > 1 mW and sub-milliwatt threshold pump powers at 1.6 $\mu$m.

Latest developments in nanophotonics associated with advantageous use of surface plasmon polaritons, hybrid excitations involving free electron oscillationsin metals and electromagnetic fields in dielectrics, are overviewed. Special attention is given to the progress in ultra-compact photonic circuitry, including modulators and detectors, and plasmonic metasurfaces dynamically controlling...