Quantum teleportation between moving detectors in a quantum field

TL;DR

This paper investigates quantum teleportation between moving detectors in a relativistic quantum field, revealing how relativistic motion and environmental effects influence fidelity and entanglement dynamics.

Contribution

It introduces a model of continuous-variable quantum teleportation using Unruh-DeWitt detectors in relativistic motion, analyzing fidelity and entanglement behavior under these conditions.

Findings

Fidelity drops below classical limits before entanglement vanishes.

Quantum state distortion can suppress fidelity despite strong entanglement.

Entanglement dynamics in different frames are not directly linked to teleportation fidelity.

Abstract

We consider the quantum teleportation of continuous variables modeled by Unruh-DeWitt detectors coupled to a common quantum field initially in the Minkowski vacuum. An unknown coherent state of an Unruh-DeWitt detector is teleported from one inertial agent (Alice) to an almost uniformly accelerated agent (Rob, for relativistic motion), using a detector pair initially entangled and shared by these two agents. The averaged physical fidelity of quantum teleportation, which is independent of the observer's frame, always drops below the best fidelity value from classical teleportation before the detector pair becomes disentangled with the measure of entanglement evaluated around the future lightcone of the joint measurement event by Alice. The distortion of the quantum state of the entangled detector pair from the initial state can suppress the fidelity significantly even when the detectors are still strongly entangled around the lightcone. We point out that the dynamics of entanglement of the detector pair observed in Minkowski frame or in quasi-Rindler frame are not directly related to the physical fidelity of quantum teleportation in our setup. These results are useful as a guide to making judicious choices of states and parameter ranges and estimation of the efficiency of quantum teleportation in relativistic quantum systems under environmental influences.