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arXiv · 1708.00296

Multiphoton interference in quantum Fourier transform circuits and applications to quantum metrology

Zu-En Su·Yuan Li·Peter P. Rohde·He-Liang Huang·Xi-Lin Wang·Li Li·Nai-Le Liu·Jonathan P. Dowling·Chao-Yang Lu·Jian-Wei Pan
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Abstract

Quantum Fourier transforms (QFT) have gained increased attention with the rise of quantum walks, boson sampling, and quantum metrology. Here we present and demonstrate a general technique that simplifies the construction of QFT interferometers using both path and polarization modes. On that basis, we first observed the generalized Hong-Ou-Mandel effect with up to four photons. Furthermore, we directly exploited number-path entanglement generated in these QFT interferometers and demonstrated optical phase supersensitivities deterministically.

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Zu-En Su, Yuan Li, Peter P. Rohde, He-Liang Huang, Xi-Lin Wang, Li Li, Nai-Le Liu, Jonathan P. Dowling, Chao-Yang Lu, Jian-Wei Pan. 2017-08-01. Multiphoton interference in quantum Fourier transform circuits and applications to quantum metrology. https://doi.org/10.1103/physrevlett.119.080502

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