Photonics for Quantum (PfQ)

Interference of photons and polarization-based quantum state tomography through emulated atmospheric turbulence

Keith A. Wyman, Noah S. Everett, Anil K. Patnaik

Published Aug 2, 2024• 0 citations

Abstract

To study long-distance free-space quantum communication links, the Air Force Institute of Technology (AFIT) simulated, designed, built, and characterized an atmospheric turbulence simulator (ATS) with the Fried parameter ranging from 0≤ D⁄r_0 <18.2. The ATS was integrated with a non-turbulent path to conduct quantum interferometric experiments such as the heralded single photon g^2 (τ), and the two-photon Hong-Ou-Mandel (HOM) measurement. We observed that g^2 (0) increased to 1 and that the visibility of the HOM dip significantly decreased in moderate turbulence . Additionally, we tested the reconstruction of polarized-entangled photonic states in various turbulence regimes, and as expected, turbulence weakly affected the reconstruction of the polarization states. This presentation details the experimental setup, results, and analysis of those experiments.

DOI: 10.1117/12.3032297

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