Device-independent certification of the teleportation of a qubit

TL;DR

This paper develops a method to certify quantum teleportation of a qubit in a black box scenario without relying on active compensation, using observed statistics to distinguish quantum from classical simulations.

Contribution

It introduces a device-independent certification approach for qubit teleportation that accounts for active compensation and provides bounds based on observed data.

Findings

Classical simulation can fake perfect teleportation with active compensation.

Without active compensation, classical simulation is necessarily imperfect.

Bounds are provided for certifying quantumness using observed statistics.

Abstract

We want to certify in a black box scenario that two parties simulating the teleportation of a qubit are really using quantum resources. If active compensation is part of the simulation, perfect teleportation can be faked with purely classical means. If active compensation is not implemented, a classical simulation is necessarily imperfect: in this case, we provide bounds for certification of quantumness using only the observed statistics. The usual figure of merit, namely the average fidelity of teleportation, turns out to be too much of a coarse-graining of the available statistical information in the case of a black-box assessment.