Criterion for k-separability in mixed multipartite systems

TL;DR

This paper introduces easily computable criteria for quantum k-separability in mixed multipartite systems, providing strong tests for k=2 and novel criteria for other cases, with practical experimental implementation.

Contribution

It develops new, computationally simple criteria for quantum k-separability applicable to all cases, including those lacking existing methods.

Findings

Criteria are as strong as the best known for k=2

New criteria are introduced for k>2 cases

Criteria can be implemented experimentally

Abstract

Using a recently introduced framework, we derive criteria for quantum k-separability, which are very easily computed. In the case k = 2, our criteria are equally strong to the best methods known so far, while in all other cases there are currently no comparable criteria known. We also show how the criteria can be implemented experimentally.