Optical nonclassicality test based on third-order intensity correlations

• Main Authors: Rigovacca, L., Kolthammer, W. S., Kim, M. S., Di Franco, Carlo
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2018
• Subjects: Third-order Intensity Correlations; Quantum Mechanics
• Online Access: https://hdl.handle.net/10356/85160; http://hdl.handle.net/10220/45156
• Institution: Nanyang Technological University

We develop a nonclassicality criterion for the interference of three delayed, but otherwise identical, light fields in a three-mode Bell interferometer. We do so by comparing the prediction of quantum mechanics with those of a classical framework in which independent sources emit electric fields with random phases. In particular, we evaluate third-order correlations among output intensities as a function of the delays, and show how the presence of a correlation revival for small delays cannot be explained by the classical model of light. The observation of a revival is thus a nonclassicality signature, which can be achieved only by sources with a photon-number statistics that is highly sub-Poissonian. Our analysis provides strong evidence for the nonclassicality of the experiment discussed by Menssen et al. [Phys. Rev. Lett. 118, 153603 (2017)], and shows how a collective “triad” phase affects the interference of any three or more light fields, irrespective of their quantum or classical character.