English

Optimal conditions for Bell test using spontaneous parametric down-conversion sources

Quantum Physics 2019-01-02 v1

Abstract

We theoretically and experimentally investigate the optimal conditions for the Bell experiment using spontaneous parametric down conversion (SPDC) sources. In theory, we show that relatively large average photon number (typically \sim0.5) is desirable to observe the maximum violation of the Clauser-Horne-Shimony-Holt (CHSH) inequality. In experiment, we perform the Bell experiment without postselection using polarization entangled photon pairs at 1550 nm telecommunication wavelength generated from SPDC sources. While the violation of the CHSH inequality is not directly observed due to the overall detection efficiencies of our system, the experimental values agree well with those obtained by the theory with experimental imperfections. Furthermore, in the range of the small average photon numbers (0.1\leq0.1), we propose and demonstrate a method to estimate the ideal CHSH value intrinsically contained in the tested state from the lossy experimental data without assuming the input quantum state.

Keywords

Cite

@article{arxiv.1808.08370,
  title  = {Optimal conditions for Bell test using spontaneous parametric down-conversion sources},
  author = {Yoshiaki Tsujimoto and Kentaro Wakui and Mikio Fujiwara and Kazuhiro Hayasaka and Shigehito Miki and Hirotaka Terai and Masahide Sasaki and Masahiro Takeoka},
  journal= {arXiv preprint arXiv:1808.08370},
  year   = {2019}
}

Comments

9 pages, 5 figures

R2 v1 2026-06-23T03:43:33.115Z