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arXiv · 2402.07056

Efficient ($\sim$10$\%$) Generation of Vacuum Ultraviolet Femtosecond Pulses via Four-Wave Mixing in Hollow-Core Fibers

Ruaridh Forbes·Paul Hockett·Quentin Leterrier·Rune Lausten
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Abstract

We report the generation of the 5th harmonic of Ti:sapphire, at 160 nm, with more than 4~$\mu$J of pulse energy, and a pulse length of 37 fs with a 1 kHz repetition rate. The VUV pulses are produced using Four-Wave Difference Frequency Mixing (FWDFM) in a helium-filled stretched Hollow-Core Fiber (HCF), driven by a pump at 267 nm and seeded at 800 nm. Guided by simulations using Luna.jl, we are able to optimize the process carefully. The result is a conversion efficiency of $\sim$10$\%$ from the 267 nm pump beam, rivaling the efficient optical mixing schemes in nonlinear crystals.

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Ruaridh Forbes, Paul Hockett, Quentin Leterrier, Rune Lausten. 2024-02-10. Efficient ($\sim$10$\%$) Generation of Vacuum Ultraviolet Femtosecond Pulses via Four-Wave Mixing in Hollow-Core Fibers. https://arxiv.org/abs/2402.07056

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