Experimental observation of three-photon superbunching in linear optical system

TL;DR

This paper reports the first experimental observation of three-photon superbunching in a linear optical system using superbunching pseudothermal light, enhancing understanding of third-order interference and improving ghost imaging visibility.

Contribution

It demonstrates three-photon superbunching in a linear optical setup, revealing the role of indistinguishable three-photon paths and interference in quantum optics.

Findings

First observation of three-photon superbunching in linear optics

Enhanced ghost imaging visibility due to superbunching

Constructive-destructive three-photon interference explained

Abstract

Three-photon superbunching is experimentally observed with the recently proposed superbunching pseudothermal light. To the best of our knowledge, it is the first time that three-photon superbunching is observed in linear optical system. From the quantum optics point of view, three-photon superbunching is interpreted as the result of constructive-destructive three-photon interference. The key to observe three-photon superbunching in superbunching pseudothermal light is that all the different ways to trigger a three-photon coincidence count are in principle indistinguishable, which is experimentally guaranteed by putting a pinhole before each rotating groundglass to ensure that all the passed photons are within one coherence area. The observed three-photon superbunching is helpful to increase the visibility of ghost imaging and understand the physics of third-order interference of light.