Single photon wavefront-splitting interference: An illustration of the light quantum in action

TL;DR

This paper demonstrates single-photon wavefront-splitting interference using a diamond nanocrystal, showcasing real-time fringe buildup and confirming single-photon behavior through path detection experiments.

Contribution

It introduces a novel experimental setup for observing single-photon interference with real-time imaging and path discrimination, illustrating quantum light behavior.

Findings

Real-time imaging of single-photon interference fringes.

Confirmation of single-photon behavior via path detection.

Successful demonstration of wavefront-splitting with a diamond nanocrystal.

Abstract

We present a new realization of the textbook experiment consisting in single-photon interference based on the pulsed, optically excited photoluminescence of a single colour centre in a diamond nanocrystal. Interferences are created by wavefront-splitting with a Fresnel's biprism and observed by registering the "single-photon clicks" with an intensified CCD camera. This imaging detector provides also a real-time movie of the build-up of the single-photon fringes. We perform a second experiment with two detectors sensitive to photons that follow either one or the other interference path. Evidence for single photon behaviour is then obtained from the absence of time coincidence between detections in these two paths.