Roadmap for Quantum Nanophotonics with Free Electrons

F. Javier García de Abajo; Albert Polman; Cruz I. Velasco; Mathieu Kociak; Luiz H. G. Tizei; Odile Stéphan; Sophie Meuret; Takumi Sannomiya; Keiichirou Akiba; Yves Auad; Armin Feist; Claus Ropers; Peter Baum; John H. Gaida; Murat Sivis; Hugo Lourenço-Martins; Luca Serafini; Johan Verbeeck; Beatrice Matilde Ferrari; Cameron J. R. Duncan; Maria Giulia Bravi; Irene Ostroman; Giovanni Maria Vanacore; Andrea Konečná; Nahid Talebi; Ethan Nussinson; Ron Ruimy; Yuval Adiv; Arthur Niedermayr; Ido Kaminer; Valerio Di Giulio; Ofer Kfir; Zhexin Zhao; Roy Shiloh; Yuya Morimoto; Martin Kozák; Peter Hommelhoff; Francesco Barantani; Fabrizio Carbone; Fatemeh Chahshouri; Wiebke Albrecht; Sergio Rey; Toon Coenen; Erik Kieft; Hoelen L. Lalandec Robert; Frank de Jong; Magdalena Solà-Garcia

arXiv · 2503.14678

Roadmap for Quantum Nanophotonics with Free Electrons

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Abstract

Over the past century, continuous advancements in electron microscopy have enabled the synthesis, control, and characterization of high-quality free-electron beams. These probes carry an evanescent electromagnetic field that can drive localized excitations and provide high-resolution information on material structures and their optical responses, currently reaching the sub-{\aa}ngstr\"om and few-meV regime. Moreover, combining free electrons with pulsed light sources in ultrafast electron microscopy adds temporal resolution in the sub-femtosecond range while offering enhanced control of the electron wave function. Beyond their exceptional capabilities for time-resolved spectromicroscopy, free electrons are emerging as powerful tools in quantum nanophotonics, on par with photons in their ability to carry and transfer quantum information, create entanglement within and with a specimen, and reveal previously inaccessible details on nanoscale quantum phenomena. This Roadmap outlines the current state of this rapidly evolving field, highlights key challenges and opportunities, and discusses future directions through a collection of topical sections prepared by leading experts.

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F. Javier García de Abajo, Albert Polman, Cruz I. Velasco, Mathieu Kociak, Luiz H. G. Tizei, Odile Stéphan, Sophie Meuret, Takumi Sannomiya, Keiichirou Akiba, Yves Auad, Armin Feist, Claus Ropers, Peter Baum, John H. Gaida, Murat Sivis, Hugo Lourenço-Martins, Luca Serafini, Johan Verbeeck, Beatrice Matilde Ferrari, Cameron J. R. Duncan, Maria Giulia Bravi, Irene Ostroman, Giovanni Maria Vanacore, Andrea Konečná, Nahid Talebi, Ethan Nussinson, Ron Ruimy, Yuval Adiv, Arthur Niedermayr, Ido Kaminer, Valerio Di Giulio, Ofer Kfir, Zhexin Zhao, Roy Shiloh, Yuya Morimoto, Martin Kozák, Peter Hommelhoff, Francesco Barantani, Fabrizio Carbone, Fatemeh Chahshouri, Wiebke Albrecht, Sergio Rey, Toon Coenen, Erik Kieft, Hoelen L. Lalandec Robert, Frank de Jong, Magdalena Solà-Garcia. 2025-03-18. Roadmap for Quantum Nanophotonics with Free Electrons. https://arxiv.org/abs/2503.14678

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