Multipartite entanglement in a Josephson junction laser

Lang, Ben; Armour, Andrew D.

Abstract

We analyze the entanglement in a model Josephson photonics system in which a dc voltage-biased Josephson junction couples a collection of cavity modes and populates them with microwave photons. Using an approximate quadratic Hamiltonian model, we study the Gaussian entanglement that develops between the modes as the Josephson energy of the system is increased. We find that the modes in the system fall into a series of blocks, with bipartite entanglement generated between modes within a given block. Tripartite entanglement between modes within a given block is also widespread, though it is limited to certain ranges of the Josephson energy. The system could provide an alternative route to generating multimode microwave entanglement, an important resource in quantum technologies, without the need for ac excitation.

Citation

Lang, B., & Armour, A. D. (2024). Multipartite entanglement in a Josephson junction laser. Physical Review A, 110(6), Article 062611. https://doi.org/10.1103/PhysRevA.110.062611

• Journal Article Type: Article
• Acceptance Date: Nov 26, 2024
• Online Publication Date: Dec 16, 2024
• Publication Date: Dec 16, 2024
• Deposit Date: Jan 2, 2025
• Publicly Available Date: Jan 2, 2025
• Journal: Physical Review A
• Print ISSN: 2469-9926
• Electronic ISSN: 2469-9934
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 110
• Issue: 6
• Article Number: 062611
• DOI: https://doi.org/10.1103/PhysRevA.110.062611
• Keywords: Coulomb blockade; Lasers; Measures of continuous variables entanglement; Quantum entanglement; Josephson junctions; Quantum master equation
• Public URL: https://nottingham-repository.worktribe.com/output/43211903
• Publisher URL: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.062611