Local sampling of the Wigner function at telecom wavelength with loss-tolerant detection of photon statistics

TL;DR

This paper demonstrates a loss-tolerant, point-by-point sampling method for the Wigner function of nonclassical light states at telecom wavelengths, enabling accurate characterization without phase reference.

Contribution

It introduces a novel loss-tolerant detection technique combined with data-pattern tomography for precise Wigner function sampling of quantum states.

Findings

Successful experimental sampling of the Wigner function at telecom wavelengths

Reliable inference of squeezing in two-mode states without phase reference

High accuracy in assessing nonclassical light states

Abstract

We report the experimental point-by-point sampling of the Wigner function for nonclassical states created in an ultrafast pulsed type-II parametric down-conversion source. We use a loss-tolerant time-multiplexed detector based on a fiber-optical setup and a pair of photon-number-resolving avalanche photodiodes. By capitalizing on an expedient data-pattern tomography, we assess the properties of the light states with outstanding accuracy. The method allows us to reliably infer the squeezing of genuine two-mode states without any phase reference.