Abstract
The ability to manipulate and observe phenomena on attosecond timescales has yielded groundbreaking insights into electron dynamics and the behaviour of matter exposed to intense light fields. The interdisciplinary field of attosecond science connects various research areas, including quantum optics, quantum chemistry and quantum information science. However, the intrinsic quantum effects in attosecond science have been largely ignored. In this Perspective, we discuss the latest theoretical and experimental advances in exploring and understanding quantum phenomena within attosecond science. We focus on distinguishing genuinely quantum observations from classical phenomena in the context of high-harmonic generation and above-threshold ionization. Additionally, we illuminate the often overlooked yet important role of entanglement in attosecond processes, elucidating its influence on experimental outcomes.
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Acknowledgements
The authors thank the organizers of the âQuantum Battles in Attoscience 2023â conference for the opportunity and support during the preparation for the discussion. L.C.-R. acknowledges financial support from the AQuA DIP project, grant number EP/J019143/1. A.F. acknowledges financial support from the Cluster of Excellence âCUI: Advanced Imaging of Matterâ of the Deutsche Forschungsgemeinschaft (DFG) - EXC 2056 - project ID 390715994, from the International Max Planck Graduate School for Ultrafast imaging & Structural Dynamics (IMPRS-UFAST) and from the Christiane Nüsslein-Vollhard-Foundation. D.D. acknowledges funding from the National Science Foundation under grant number CHE-2347622 and the European Unionâs Horizon 2020 research and innovation programme under the Marie SkÅodowska-Curie Grant agreement number 892554. P.S. acknowledges funding from the European Unionâs Horizon 2020 research and innovation programme under the Marie SkÅodowska-Curie grant agreement number 847517. Institut de Ciencies Fotoniques (ICFO) group acknowledges support from the following: Ministerio de Ciencia y Innovation Agencia Estatal de Investigaciones (R&D project CEX2019-000910-S, AEI/10.13039/501100011033, Plan National FIDEUA PID2019-106901GB-I00, FPI), Fundació Privada Cellex, Fundació Mir-Puig, Generalitat de Catalunya (AGAUR Grant number 2017 SGR 1341, CERCA programme), MICIIN with funding from European Union NextGenerationEU (PRTR-C17.I1), Generalitat de Catalunya, and EU Horizon 2020 FET-OPEN OPTOlogic (grant number 899794) and ERC AdG NOQIA. Views and opinions expressed are, however, those of the authors only and do not necessarily reflect those of the European Union, European Commission, European Climate, Infrastructure and Environment Executive Agency (CINEA), nor any other granting authority. Neither the European Union nor any granting authority can be held responsible for them.
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Cruz-Rodriguez, L., Dey, D., Freibert, A. et al. Quantum phenomena in attosecond science. Nat Rev Phys 6, 691â704 (2024). https://doi.org/10.1038/s42254-024-00769-2
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DOI: https://doi.org/10.1038/s42254-024-00769-2