Pulsewidth-switchable ultrafast source at 114 nm

Anahita Omoumi (1, 2, 3) , Michele Natile (3) , Evangelos Papalazarou (2) , Yoann Zaouter (3) , Thierry Auguste (4) , Marc Hanna (1) , Patrick Georges (1) , Marino Marsi (2)

1 Laboratoire Charles Fabry / Lasers
2 LPS - Laboratoire de Physique des Solides
3 Amplitude Systèmes
4 LIDYL - Laboratoire Interactions, Dynamiques et Lasers (ex SPAM)

Femtosecond laser sources with high repetition rate are fundamental tools enabling tabletop time-resolved and angle-resolved photoemission spectroscopy in solids. The UV and vacuum UV laser light required for the photoemission process can be generated through various frequency up-conversion techniques. We describe a VUV source at 114 nm (10.8 eV) based on an industrial grade ytterbium-doped ultrafast laser, a nonlinear pulsewidth selection stage, and two cascaded frequency tripling stages, first in crystals, second in xenon. The role of ionization in gas-based perturbative third harmonic generation phase-matching is analyzed using a simple theory, numerical simulations, and experimental data. The source features high photon flux, high repetition rate and adjustable time resolutions. Thereby, in combination with a state-of-the-art ARPES apparatus it enables the study of the electronic dynamics of the whole Brillouin zone in a large number of materials.

Domaines: Optique [physics.optics]

Anahita Omoumi, Michele Natile, Evangelos Papalazarou, Yoann Zaouter, Thierry Auguste, et al.. Pulsewidth-switchable ultrafast source at 114 nm. Optics Letters, 2023, 48 (17), pp.4625-4628. ⟨10.1364/OL.498266⟩. ⟨hal-04192119⟩