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.
@article{arxiv.1708.00296,
title = {Multiphoton interference in quantum Fourier transform circuits and applications to quantum metrology},
author = {Zu-En Su and Yuan Li and Peter P. Rohde and He-Liang Huang and Xi-Lin Wang and Li Li and Nai-Le Liu and Jonathan P. Dowling and Chao-Yang Lu and Jian-Wei Pan},
journal= {arXiv preprint arXiv:1708.00296},
year = {2024}
}
Comments
8 pages, 10 figures. To appear in Physical Review Letters