A class of exposed indecomposable positive maps

TL;DR

This paper introduces a new class of indecomposable positive maps in matrix algebras that are exposed, providing a powerful tool for distinguishing entangled states from separable ones in quantum information theory.

Contribution

It presents a novel class of exposed indecomposable positive maps in 2n x 2n matrices, expanding the toolkit for entanglement detection.

Findings

The maps are proven to be exposed and indecomposable.

These maps are dense among extremal positive maps.

They enhance the ability to discriminate entangled states.

Abstract

Exposed positive maps in matrix algebras define a dense subset of extremal maps. We provide a class of indecomposable positive maps in the algebra of 2n x 2n complex matrices with n>1. It is shown that these maps are exposed and hence define the strongest tool in entanglement theory to discriminate between separable and entangled states.