Censorship of Quantum Resources in Quantum Networks

TL;DR

This paper introduces a nonlinear censorship protocol using classical information to restrict quantum resources in networks, overcoming limitations of resource-destroying channels and enabling unbreakable censorship for certain resources.

Contribution

The work develops a novel nonlinear censorship protocol that surpasses existing limitations, enabling unbreakable control over specific quantum resources in networks.

Findings

Unbreakable censorship of imaginarity and entanglement achieved.

Limitations of resource-destroying channels identified.

Censorship not possible for quantum discord and Bell nonlocality.

Abstract

We may soon see agencies offering public access to quantum communication networks. In such networks it may be a feature that certain resources are available only to priority users or at a higher user fee, as governed by a protective agency overseeing the communication in the network. If the agency wants to restrict the general users to communicate by transmitting states that we categorize as free states of a quantum resource theory (QRT), it may employ resource-destroying (RD) channels that do not affect the free states. Such channels, however, only exist for the simplest of QRTs, putting fundamental limitations on how quantum resources can be regulated. In this work, we go beyond the present limitation by devising a nonlinear censorship protocol which makes use of classical information about the transmitted state. We study the requirement disabling malicious users from breaking the censorship. The protocol can establish an unbreakable censorship of imaginarity and entanglement, while no such censorship can be made for quantum discord and Bell nonlocality.