Simple proof of the quantum benchmark fidelity for continuous-variable quantum devices

TL;DR

This paper provides a straightforward proof of the classical fidelity limit for continuous-variable quantum devices, using state-channel duality and partial transposition, aiding in experimental validation of quantum teleportation.

Contribution

It introduces a simple, rigorous proof of the quantum benchmark fidelity for continuous-variable systems based on well-known quantum information concepts.

Findings

Derived a quantum-domain criterion linked to measured fidelities

Simplified the proof of the classical fidelity limit

Enabled experimental validation of quantum advantage

Abstract

An experimental success criterion for continuous-variable quantum teleportation and memories is to surpass a limit of the average fidelity achieved by the classical measure-and-prepare schemes with respect to a Gaussian distributed set of coherent states. We present a simple proof of the classical limit based on the familiar notions of the state-channel duality and the partial transposition. The present method enables us to produce a quantum-domain criterion associated with a given set of measured fidelities.