Purifying teleportation

TL;DR

This paper demonstrates that quantum decoherence effects can be probabilistically reversed during quantum teleportation in a network, especially for qubits, by exploiting quantum properties and specific conditions, enhancing quantum network robustness.

Contribution

It introduces a method to reverse decoherence effects during teleportation by using a second teleportation step under certain conditions, applicable to qubits and higher-dimensional systems.

Findings

Decoherence can be reversed in 25% of qubit teleportation instances.

The method is effective under pure dephasing coupling with specific commutativity conditions.

The approach is demonstrated in a physical model of a qubit coupled to a bosonic bath.

Abstract

Coupling to the environment typically suppresses quantum properties of physical systems via decoherence mechanisms. This is one of the main obstacles in practical implementations of quantum protocols. In this work we show how decoherence effects can be reversed/suppressed during quantum teleportation in a network scenario. Treating the environment quantumly, we show that under a general pure dephasing coupling, performing a second teleportation step can probabilistically reverse the decoherence effects if certain commutativity conditions hold. This effect is purely quantum and most pronounced for qubit systems, where in 25 % of instances the decoherence can be reversed completely. As an example, we show the effect in a physical model of a qubit register coupled to a bosonic bath. We also analyze general $d$-dimensional systems, identifying all instances of decoherence suppression. Our results are proof-of-concept but we believe will be relevant for the emerging field of quantum networks as teleportation is the key building block of network protocols.