Generation of Tuneable Vacuum Ultraviolet Pulses Through Resonant Dispersive Wave Emission with an Ytterbium-Based Laser

Ultrafast laser pulses in the vacuum ultraviolet (VUV, 100–200 nm) are an important tool for next-generation ultrafast science, as virtually all materials and chemical compounds exhibit strong electronic absorption resonances in this spectral region. To address important photophysical dynamics at their natural timescales, few-femtosecond pulses are required. Resonant dispersive wave (RDW) emission in gas-filled hollow-core waveguides is a promising route to addressing this need. Low-energy VUV RDW emission in anti-resonant fibre has already been used in proof-of-concept experiments [1], but guidance resonances inherent to this type of waveguide limit the tuning range, and the small core sizes limit the pulse energy. Exploiting the same process at much higher pulse energy in simple hollow capillary fibres (HCFs) creates continuously tuneable microjoule-level pulses across the vacuum and deep ultraviolet [2]. VUV RDW emission in HCF has so far been restricted to systems driven by titanium-doped sapphire laser amplifiers. The increased pulse repetition rate and improved reliability offered by ytterbium-based drive lasers has yet to be exploited.