Optical detection and storage of entanglement in plasmonically coupled quantum-dot qubits

Journal Article · Mon Mar 25 00:00:00 EDT 2019 · Physical Review A

DOI:https://doi.org/10.1103/PhysRevA.99.032339· OSTI ID:1558990

Otten, M. ^[1]; Gray, S. K. ^[1]; Kolmakov, G. V. ^[2]

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1. Argonne National Lab. (ANL), Argonne, IL (United States)
2. City Univ. of New York, Brooklyn, NY (United States)

Recent proposals and advances in quantum simulations, quantum cryptography, and quantum communications substantially rely on quantum entanglement formation. Contrary to the conventional wisdom that dissipation destroys quantum coherence, coupling with a dissipative environment can also generate entanglement. We consider a system composed of two quantum-dot qubits coupled with a common, damped surface plasmon mode; each quantum dot is also coupled to a separate photonic cavity mode. Cavity quantum electrodynamics calculations show that upon optical excitation by a femtosecond laser pulse, entanglement of the quantum-dot excitons occurs, and the time evolution of the g⁽²⁾ pair correlation function of the cavity photons is an indicator of the entanglement. We also show that the degree of entanglement is conserved during the time evolution of the system. Furthermore, if coupling of the photonic cavity and quantum-dot modes is large enough, the quantum-dot entanglement can be transferred to the cavity modes to increase the overall entanglement lifetime. This latter phenomenon can be viewed as a signature of entangled, long-lived quantum-dot exciton-polariton formation. In conclusion, the preservation of total entanglement in the strong-coupling limit of the cavity-quantum-dot interactions suggests a novel means of entanglement storage and manipulation in high-quality optical cavities.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Office of Workforce Development for Teachers & Scientists (WDTS); USDOE Office of Science (SC), Workforce Development for Teachers and Scientists (WDTS) (SC-27)
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1558990
• Alternate ID(s): OSTI ID: 1546348
• Journal Information: Physical Review A, Journal Name: Physical Review A Journal Issue: 3 Vol. 99; ISSN PLRAAN; ISSN 2469-9926
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS