Attosecond vortex pulse trains

Alba de las Heras; David Schmidt; Julio San Román; Javier Serrano; Daniel Adams; Luis Plaja; Charles G. Durfee; Carlos Hernández-García

arXiv · 2402.15225

Attosecond vortex pulse trains

Alba de las Heras·David Schmidt·Julio San Román·Javier Serrano·Daniel Adams·Luis Plaja·Charles G. Durfee·Carlos Hernández-García

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Abstract

The landscape of ultrafast structured light pulses has recently evolved driven by the capability of high-order harmonic generation (HHG) to up-convert orbital angular momentum (OAM) from the infrared to the extreme-ultraviolet (EUV) spectral regime. Accordingly, HHG has been proven to produce EUV vortex pulses at the femtosecond timescale. Here we demonstrate the generation of attosecond vortex pulse trains, i.e. a succession of attosecond pulses with a helical wavefront, resulting from the synthesis of a comb of EUV high-order harmonics with the same OAM. By driving HHG with a polarization tilt-angle fork grating, two spatially separated circularly polarized high-order harmonic beams with order-independent OAM are created. Our work opens the route towards attosecond-resolved OAM light-matter interactions.

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Alba de las Heras, David Schmidt, Julio San Román, Javier Serrano, Daniel Adams, Luis Plaja, Charles G. Durfee, Carlos Hernández-García. 2024-02-23. Attosecond vortex pulse trains. https://arxiv.org/abs/2402.15225

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