Exclusion Principle for Quantum Dense Coding

TL;DR

This paper establishes an exclusion principle for quantum dense coding, showing that in multipartite states, only one bipartite reduction can have a quantum advantage, and this principle is robust and independent of entanglement distribution.

Contribution

It introduces a novel exclusion principle for dense coding capacities in multipartite quantum states, extending to arbitrary dimensions and parties, and derives a strict monogamy relation.

Findings

No two bipartite reductions of a tripartite state can both have quantum dense coding advantage.

The exclusion principle holds for arbitrary pure or mixed states and is noise-robust.

A strict monogamy relation for multi-party classical capacities is established.

Abstract

We show that the classical capacity of quantum states, as quantified by its ability to perform dense coding, respects an exclusion principle, for arbitrary pure or mixed three-party states in any dimension. This states that no two bipartite states which are reduced states of a common tripartite quantum state can have simultaneous quantum advantage in dense coding. The exclusion principle is robust against noise. Such principle also holds for arbitrary number of parties. This exclusion principle is independent of the content and distribution of entanglement in the multipartite state. We also find a strict monogamy relation for multi-port classical capacities of multi-party quantum states in arbitrary dimensions. In the scenario of two senders and a single receiver, we show that if two of them wish to send classical information to a single receiver independently, then the corresponding dense coding capacities satisfy the monogamy relation, similar to the one for quantum correlations.