Using CF₄ and SF₆ gases and a home-built nanosecond pump laser, we achieved first Stokes conversion efficiencies of up to ~70%. These results demonstrate the feasibility of generating yellow laser emission via Raman conversion of a 1.064 μm laser to 1.16 μm in a gas-filled hollow-core fiber, followed by frequency doubling (second-harmonic generation). Methane (CH₄) has also proven to be an efficient Raman medium, enabling high conversion efficiencies from 1 μm to 1.5 μm using nanosecond pulses. By carefully selecting the pump wavelength, we can generate wavelengths that are otherwise difficult to access.
This platform further enables exploration of Raman conversion into the mid-infrared (mid-IR) spectral region, targeting specific wavelengths of scientific and technological interest.
This research is ongoing.