# Universal trade-off relation between coherence and intrinsic concurrence for two-qubit states

## TL;DR

This paper introduces a new measure called intrinsic concurrence that reveals a universal trade-off relation with coherence in two-qubit states, enhancing understanding of quantum resource interconversion.

## Contribution

The paper proposes the intrinsic concurrence measure and establishes a universal trade-off relation with coherence for two-qubit states, linking entanglement and coherence.

## Key findings

- Intrinsic concurrence is always complementary to coherence.
- The trade-off relation applies across different noise channels.
- Provides a theoretical basis for resource interconversion in quantum systems.

## Abstract

Entanglement and coherence are two essential quantum resources for quantum information processing. A natural question arises of whether there are direct link between them. And by thinking about this question, we propose a new measure for quantum state that contains concurrence and is called intrinsic concurrence. Interestingly, we discover that the intrinsic concurrence is always complementary to coherence. Note that the intrinsic concurrence is related to the concurrence of a special pure state ensemble. In order to explain the trade-off relation more intuitively, we apply it in some composite systems composed by a single-qubit state coupling four typical noise channels with the aim at illustrating their mutual transformation relationship between their coherence and intrinsic concurrence. This unified trade-off relation will provide more flexibility in exploiting one resource to perform quantum tasks and also provide credible theoretical basis for the interconversion of the two important quantum resources.