Entropic Entanglement Criteria for Continuous Variables

TL;DR

This paper introduces entropy-based entanglement criteria for continuous variable quantum systems that outperform traditional variance-based tests and are practical for experimental implementation.

Contribution

It develops new entanglement criteria using Shannon entropy that are more sensitive than second-order moment methods and require only two quadrature measurements.

Findings

Criteria are more sensitive than variance-based tests.

Equivalent to variance product tests for Gaussian states.

Applicable with only a pair of quadrature measurements.

Abstract

We derive several entanglement criteria for bipartite continuous variable quantum systems based on the Shannon entropy. These criteria are more sensitive than those involving only second-order moments, and are equivalent to well-known variance product tests in the case of Gaussian states. Furthermore, they involve only a pair of quadrature measurements, and will thus should prove extremely useful the experimental identification of entanglement.