Quantum correlation measure in arbitrary bipartite systems

TL;DR

This paper introduces a new quantum correlation measure for bipartite systems based on skew information, which is effective, analytically calculable, and relates to quantum metrology, with exact results for many states.

Contribution

It proposes a novel quantum correlation measure using skew information that is both theoretically sound and practically calculable for arbitrary bipartite states.

Findings

The measure inherits properties like contractivity from skew information.

Exact quantum correlation expressions are derived for various states.

The measure's relation to quantum metrology is established.

Abstract

A definition of quantum correlation is presented for an arbitrary bipartite quantum state based on the skew information. This definition not only inherits the good properties of skew information such as the contractivity and so on, but also is effective and almost analytically calculated for any bipartite quantum states. We also reveal the relation between our measure and quantum metrology. As applications, we give the exact expressions of quantum correlation for many states, which provides a direct support for our result.