Characterization of phase-averaged coherent states

TL;DR

This paper provides a comprehensive theoretical and experimental analysis of phase-averaged coherent states, highlighting their properties, manipulation, and potential in quantum communication and key distribution.

Contribution

It introduces a formalism for describing phase-averaged coherent states and demonstrates their experimental manipulation and characterization, confirming theoretical predictions.

Findings

Experimental results agree with theoretical models.

Manipulation with linear optical elements is effective.

Non-Gaussianity measures and mutual information confirm state quality.

Abstract

We present the full characterization of phase-randomized or phase-averaged coherent states, a class of states exploited in communication channels and in decoy state-based quantum key distribution protocols. In particular, we report on the suitable formalism to analytically describe the main features of this class of states and on their experimental investigation, that results in agreement with theory. We also show the results we obtained by manipulating the phase-averaged coherent states with linear optical elements and testify their good quality by employing some non-Gaussianity measures and the concept of mutual information.