Demonstration of unpartible entanglement
Abstract
We report on the first experimental verification of mode-independent entanglement. Commonly, the entanglement of a state is firmly based on pre-defined parties that are correlated, and the state might be disentangled when the definition of the parties is changed. Exceeding this party-dependent concept, we realize a type of quantum entanglement that persists even if the parties, in our case modes, are transformed. This safeguards the performance of entanglement in real-world applications, such as quantum communication settings involving noise and untrusted parties. For the state generation, we present an experimental scheme based on a fully reconfigurable temporally multiplexed interferometer with measurement-induced nonlinearities, which generates heralded two-photon states in two modes that are entangled for all choices of orthonormal mode basis. For the certification process, we utilize a tailored quantum-state tomography, achieving fidelities that validate the presence of mode-independent entanglement as a resilient and operationally advantageous quantum correlation.
Keywords
Cite
@article{arxiv.2606.30468,
title = {Demonstration of unpartible entanglement},
author = {Philip Held and Laura Ares and Federico Pegoraro and Jonas Lammers and Benjamin Brecht and Jan Sperling and Christine Silberhorn},
journal= {arXiv preprint arXiv:2606.30468},
year = {2026}
}