Strong superadditivity relations for multiqubit systems

TL;DR

This paper explores superadditivity relations of quantum coherence in multiqubit systems, presenting generalized inequalities that improve upon existing bounds and deepen understanding of quantum coherence distribution.

Contribution

It introduces generalized superadditivity inequalities for multiqubit coherence based on the $ ext{l}_1$ norm, extending and tightening previous results.

Findings

Derived general superadditivity inequalities for multiqubit states.

Showed the new inequalities are tighter than existing ones with specific examples.

Unified existing superadditivity relations as special cases.

Abstract

We investigate the distributions of quantum coherence characterized by superadditivity relations in multipartite quantum systems. General superadditivity inequalities based on the $\alpha$th ($\alpha\geqslant 1$) power of $l_1$ norm of coherence are presented for multiqubit states, which include the existing ones as special cases. Our result is shown to be tighter than the existing one by a specific example.