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  • Open Access

Taming plasmonic nanocavities for persistent entanglement

Angus Crookes, Ben Yuen, and Angela Demetriadou*

  • *Contact author: a.demetriadou@bham.ac.uk
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Phys. Rev. B 112, 085427 – Published 28 August, 2025

DOI: https://doi.org/10.1103/skc6-gnyr

Abstract

Recent rapid advances in quantum nanoplasmonics offer the potential for accessing quantum phenomena at room temperature. Despite this, entangled states have not yet been realized, and remain an outstanding challenge. In this work, we demonstrate how entanglement emerges in plasmonic nanocavities, which are inherently multimode, and demonstrate the conditions necessary for entanglement to persist. We find that, in general, these conditions are broken due to coupling with multiple plasmonic modes of different parity. We address this challenge with a new nanocavity design that supports high selective coupling to a single mode, enabling the robust generation of persistent entanglement in nanoplasmonics. Our results open exciting prospects for leveraging simple plasmonic setups in ambient conditions for applications in quantum communication, sensing, and rapid quantum memories.

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Phys. Rev. B 112, 085427– Published 28 August, 2025
  • Received 23 October 2024
  • Revised 30 April 2025
  • Accepted 27 June 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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