Non-Gaussianity of quantum states: an experimental test on single-photon added coherent states

TL;DR

This paper experimentally tests the non-Gaussianity of quantum states, specifically single-photon added coherent states, using a criterion based on conditional entropy, highlighting the measure's reliability and the impact of experimental imperfections.

Contribution

It applies a new experimentally accessible criterion to quantify non-Gaussianity in single-photon added coherent states, demonstrating its effectiveness and sensitivity.

Findings

The criterion reliably measures non-Gaussianity in experimental states.

Experimental imperfections significantly affect the non-Gaussianity measure.

The method provides a sensitive tool for characterizing non-Gaussian quantum states.

Abstract

Non Gaussian states and processes are useful resources in quantum information with continuous variables. An experimentally accessible criterion has been proposed to measure the degree of non Gaussianity of quantum states, based on the conditional entropy of the state with a Gaussian reference. Here we adopt such criterion to characterise an important class of non classical states, single-photon added coherent states. Our studies demonstrate the reliability and sensitivity of this measure, and use it to quantify how detrimental is the role of experimental imperfections in our realisation.