Experimental determination of the degree of quantum polarisation of continuous variable states

TL;DR

This paper introduces a novel method for characterizing the polarization of continuous-variable quantum states by resolving the Stokes vector for each excitation manifold, providing a more detailed description than traditional methods.

Contribution

The paper presents an experimental technique to determine the Stokes vector of each excitation manifold separately, enhancing polarization characterization of CV quantum states beyond traditional approaches.

Findings

The method accurately characterizes states with indeterminate photon numbers.

Experimental results confirm the advantages of the new characterization method.

The approach provides a richer description for Gaussian states.

Abstract

We demonstrate excitation-manifold resolved polarisation characterisation of continuous-variable (CV) quantum states. In contrast to traditional characterisation of polarisation that is based on the Stokes parameters, we experimentally determine the Stokes vector of each excitation manifold separately. Only for states with a given photon number does the methods coincide. For states with an indeterminate photon number, for example Gaussian states, the employed method gives a richer and more accurate description. We apply the method both in theory and in experiment to some common states to demonstrate its advantages.