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arXiv · 2604.16107

Entanglement and photoelectron holography in dissociative photoionization: molecular quantum eraser

Sebastian Hell·Paul Winter·Martin Gärttner·Julian Späthe·Saurabh Mhatre·Dejan B. Milošević·Gerhard G. Paulus·Manfred Lein·Matthias Kübel
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Abstract

In a double-slit experiment with a bipartite system, the visibility of interference fringes depends on the availability of which-way information. Here, we report the formation of a Bell-like state of photoelectron and residual ion in the multiphoton dissociative ionization of the D$_2$ molecule. Evidence for entanglement is provided by the correlated emission directions of photoelectron and ion, which is observed using a COLTRIMS reaction microscope. In the presence of this correlation, the holographic interference fringes contained in the photoelectron momentum distributions are suppressed, indicating the existence of which-way information. We show that the which-way information is erased, and the interference pattern is restored, when a single ionic state is selected. The experimental observations and conclusions are fully supported by the numerical solution of the electronic-nuclear time-dependent Schr\"odinger equation. Our work demonstrates that coincidence spectroscopy of ions and electrons is a powerful method for studying fundamental concepts of quantum information science within the context of ultrafast light-matter interactions.

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Sebastian Hell, Paul Winter, Martin Gärttner, Julian Späthe, Saurabh Mhatre, Dejan B. Milošević, Gerhard G. Paulus, Manfred Lein, Matthias Kübel. 2026-04-17. Entanglement and photoelectron holography in dissociative photoionization: molecular quantum eraser. https://arxiv.org/abs/2604.16107

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