Multipartite concurrence of W-class states based on sub-partite quantum systems

TL;DR

This paper derives analytical formulas and bounds for multipartite concurrence in W-class states, enhancing entanglement detection in complex quantum systems.

Contribution

It provides new analytical formulas and relations for multipartite concurrence in W-class states, improving entanglement detection methods.

Findings

Derived explicit formulas for N-partite W-class states

Established relations between multipartite and (N-1)-partite concurrence

Presented improved lower bounds for mixed state entanglement detection

Abstract

We study the concurrence for arbitrary N-partite W-class states based on the (N-1)-partite partitions of subsystems by taking account to the structures of W-class states. By using the method of permutation and combination we give analytical formula of concurrence and some elegant relations between the multipartite concurrence and the (N-1)-partite concurrence for arbitrary multipartite W-class states. Applying these relations we present better lower bounds of concurrence for multipartite mixed states. An example is given to demonstrate that our lower bounds can detect more entanglements.