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arXiv · 2406.10331

A 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
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Abstract

Optical quantum information processing critically relies 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 multi-photon components, decreasing the overall process fidelity. Here, we introduce a novel 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.

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Beate E. Asenbeck, Akito Kawasaki, Ambroise Boyer, Tom Darras, Alban Urvoy, Akira Furusawa, Julien Laurat. 2024-06-14. A Hybrid Approach to Mitigate Errors in Linear Photonic Bell-State Measurement for Quantum Interconnects. https://doi.org/10.1103/prxquantum.5.030331

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