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

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 نشر من قبل Zu-En Su
 تاريخ النشر 2017
  مجال البحث فيزياء
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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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