Probing the negative Wigner function of a pulsed single photon point by point

TL;DR

This paper demonstrates a method to directly observe the negative Wigner function of a pulsed single photon by point-by-point phase space probing using loss-tolerant photon-number resolving detection, revealing quantum features with high mode sensitivity.

Contribution

It introduces a novel approach for directly measuring the negative Wigner function of pulsed single photons with high mode sensitivity using photon-number resolving detection.

Findings

Successfully observed the negative Wigner function region.

Demonstrated phase space oscillations of photon statistics.

Revealed the single-mode nature of the generated photon state.

Abstract

We investigate quantum properties of pulsed light fields point by point in phase space. We probe the negative region of the Wigner function of a single photon generated by the means of waveguided parametric down-conversion. This capability is achieved by employing loss-tolerant photon-number resolving detection, allowing us to directly observe the oscillations of the photon statistics in dependence of applied displacements in phase space. Our scheme is highly mode sensitive and can reveal the single-mode character of the signal state.