Measuring the quantum state of photoelectrons
Abstract A photoelectron, emitted due to the absorption of light quanta as described by the photoelectric effect, is often characterized experimentally by a classical quantity, its momentum. However, since the photoelectron is a quantum object, its rigorous characterization requires the reconstruction of the complete quantum state, the photoelectron’s density matrix. Here we use quantum-state tomography to fully characterize photoelectrons emitted from helium and argon atoms upon absorption of ultrashort, extreme ultraviolet light pulses. While in helium we measure a pure photoelectronic state, in argon, spin–orbit interaction induces entanglement between the ion and the photoelectron, leading to a reduced purity of the photoelectron state. Our work shows how state tomography gives new insights into the fundamental quantum aspects of light-induced electronic processes in matter, bridging the fields of photoelectron spectroscopy and quantum information and offering new spectroscopic possibilities for quantum technology.
Authors
- Christoph Dittel (ORCID: https://orcid.org/0000-0002-5373-5196)
- Vénus Poulain (ORCID: https://orcid.org/0000-0003-2218-1845)
- Sizuo Luo (ORCID: https://orcid.org/0000-0002-8969-5958)
- Hugo Laurell (ORCID: https://orcid.org/0000-0002-2059-2715)
- David Busto (ORCID: https://orcid.org/0000-0003-4311-3315)
- Daniel Finkelstein‐Shapiro (ORCID: https://orcid.org/0000-0001-8015-5376)
- Richard J. Squibb (ORCID: https://orcid.org/0000-0001-6708-8631)
- Cord L. Arnold (ORCID: https://orcid.org/0000-0003-4249-411X)
- Robin Weissenbilder (ORCID: https://orcid.org/0000-0002-8081-3727)
- Mattias Ammitzböll
- Andreas Buchleitner
- Chen Guo (ORCID: https://orcid.org/0000-0003-3532-143X)
- Anton Frisk Kockum (ORCID: https://orcid.org/0000-0002-2534-3021)
- C. Leon M. Petersson (ORCID: https://orcid.org/0000-0002-4208-1684)
- Mathieu Gisselbrecht (ORCID: https://orcid.org/0000-0003-0257-7607)
- R. Feifel (ORCID: https://orcid.org/0000-0001-5234-3935)
- Eva Lindroth (ORCID: https://orcid.org/0000-0003-3444-1317)
- A. L’Huillier (ORCID: https://orcid.org/0000-0002-1335-4022)
- Hugo Söderberg
- Shahnawaz Ahmed
Institutions
- University of Freiburg (DE)
- Stockholm University (SE)
- Lund University (SE)
- AlbaNova (SE)
- Chalmers University of Technology (SE)
- University of Gothenburg (SE)
- Universidad Nacional Autónoma de México (MX)
Publication Details
- Journal
- Nature Photonics
- Published
- 2025-01-29
- DOI
- https://doi.org/10.1038/s41566-024-01607-8
- Citations
- 23
- Primary Topic
- Laser-Matter Interactions and Applications
- Type
- article
- Field-Weighted Citation Impact
- 28.68
Funders
- Lunds Universitet
- Knut och Alice Wallenbergs Stiftelse
- Vetenskapsrådet
- Freiburg Institute for Advanced Studies, Albert-Ludwigs-Universität Freiburg
- Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México
- Wallenberg Centre for Molecular and Translational Medicine