Estimation of the CHSH Parameter Using HOM Interference

• Published in: IEEE transactions on quantum engineering Vol. 3; pp. 1 - 10
• Main Authors: Brewster, Richard A., Goldhar, Julius, Morris, Mark, Baumgartner, Gerald, Chembo, Yanne K.
• Format: Journal Article
• Language: English
• Published: New York IEEE 2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Crystals; Detectors; Error analysis; Experiments; Interference; optical interferometry; Optical variables measurement; Parameters; Photonics; Quantum communication; Quantum entanglement; Quantum mechanics; Quantum optics
• ISSN: 2689-1808; 2689-1808
• DOI: 10.1109/TQE.2022.3152170

The Clauser-Horne-Shimony-Holt (CHSH) experiment is an essential test of nonlocality in quantum mechanics and can be used to validate the principle of entanglement. In addition to verifying entanglement, the measurable CHSH parameter can also be used to gauge the quality of the entanglement present in a system. The measurement of Hong-Ou-Mandel (HOM) interference is another important fundamental experiment in quantum optics that measures the indistinguishability of a pair of photons. In this article, we demonstrate how the results of a HOM interference experiment, a relatively simple experiment, can be used to obtain an estimate for the value of the CHSH <inline-formula><tex-math notation="LaTeX">S</tex-math></inline-formula> parameter, which is a more complicated measurement. We experimentally demonstrate that the HOM interference technique is capable of providing an estimate of the value of the CHSH parameter that is within one standard deviation of measurement error when spectral impairments are present. We expect that this technique will aid in the calibration of quantum optical systems.