Characterizing Entanglement Sources

TL;DR

This paper presents a method for characterizing entanglement sources using finite, possibly non-tomographically complete measurements, providing probabilistic assessments and entanglement estimates with model comparison techniques.

Contribution

It introduces a novel approach that does not require complete measurements and incorporates model selection criteria for entanglement source characterization.

Findings

Provides a probabilistic measure of entanglement generation

Estimates entanglement measures with error bars

Uses Akaike and Bayesian criteria for model assessment

Abstract

We discuss how to characterize entanglement sources with finite sets of measurements. The measurements do not have to be tomographically complete, and may consist of POVMs rather than von Neumann measurements. Our method yields a probability that the source generates an entangled state as well as estimates of any desired calculable entanglement measures, including their error bars. We apply two criteria, namely Akaike's information criterion and the Bayesian information criterion, to compare and assess different models (with different numbers of parameters) describing entanglement-generating devices. We discuss differences between standard entanglement-verificaton methods and our present method of characterizing an entanglement source.