Gouy phase engineering of self-splitting quantum correlations

TL;DR

This paper demonstrates how Gouy phase engineering can induce self-splitting quantum correlations in spontaneous parametric down conversion, enabling novel quantum interference effects for quantum metrology.

Contribution

It introduces a method to transfer structured pump beam modes to quantum correlations, creating self-splitting and recombining two-photon states with potential applications.

Findings

Observed heralded single-photon interference.

Demonstrated two-photon NOON state interference.

Showed propagation of joint two-photon probability like a self-splitting beam.

Abstract

In this work, we demonstrate the effect of self-splitting spatial quantum correlations induced by Gouy phase engineering. In the process of spontaneous parametric down conversion the pump beam is structured with a mode superposition that produces a dynamical splitting and recombination of the light beam. This structure is transferred to the quantum correlations between signal and idler photons. As a result the joint two-photon probability distribution propagates like a self-splitting and recombining light beam, implementing a Mach-Zehnder-like interferometer. We observe heralded single-photon interference and two-photon NOON state interference. These results open new avenues for applications in quantum metrology.