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arXiv:2406.10331 · PRX Quantum

Hybrid Approach to Mitigate Errors in Linear Photonic Bell-State Measurement for Quantum Interconnects

Beate E. Asenbeck, Akito Kawasaki, Ambroise Boyer, Tom Darras, Alban Urvoy, Akira Furusawa, Julien Laurat

Published Aug 12, 2024• 1 citation
arXivHTMLPDF

Abstract

Optical quantum information processing relies critically on Bell-state measurement, a ubiquitous operation for quantum communication and computing. Its practical realization involves the interference of optical modes and the detection of a single photon in an indistinguishable manner. Yet, in the absence of efficient photon-number-resolution capabilities, errors arise from multiphoton components, decreasing the overall process fidelity. Here, we introduce a hybrid detection scheme for Bell-state measurement, leveraging both on-off single-photon detection and quadrature conditioning via homodyne detection. We derive explicit fidelities for quantum teleportation and entanglement-swapping processes employing this strategy, demonstrating its efficacy. We also compare with photon-number-resolving detectors and find a strong advantage of the hybrid scheme in a wide range of parameters. This work provides a new tool for linear-optics schemes, with applications to quantum state engineering and quantum interconnects. Published by the American Physical Society 2024

DOI
10.1103/prxquantum.5.030331

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