Southwest Quantum Information and Technology

Quantum advantage in interferometric imaging

Presenting Author: Matthew Brown, University of Oregon
Contributing Author(s): Markus Allgaier, Valérian Thiel, Brian Smith, Michael Raymer, John Monnier

Just over 100 years ago, Michelson and Pease measured the diameter of a star using the interference of visible-spectrum light fields collected at two positions in an apertured telescope. The spatial coherence, distilled from a spatially incoherent object through propagation, between the collected light fields is guaranteed by the van Cittert-Zernike theorem. The angular resolution of the collection of apertures is limited by the separation of apertures, rather than the size of a single aperture. This technique has been employed recently in radio astronomy to image supermassive black holes. Yet, measurements in the visible spectrum are limited to comparatively short baselines due to loss or cost, whereas the radio regime circumvents this issue by measuring the electric field at each location. In 2012, Gottesman, Jennewein and Croke suggested using a nonlocally distributed single photon as a phase reference, increasing the telescope separation using quantum repeaters to overcome loss. In a first of a kind measurement, we report the use of a heralded single photon from a pulsed, parametric downconversion source as a non-local oscillator to image a double-slit intensity pattern illuminating a diffuser that has a matching single temporal-spectral mode, Lambertian scattering, and approximate spatial incoherence. Using signal-to-noise ratio per coincidence as a metric, we find that the nonlocal oscillator outperforms a weak classical local oscillator.

Read this article online: https://doi.org/10.1364/QUANTUM.2022.QM3C.1

(Session 6 : Friday from 9:15 am - 9:45 am)