Quantum teleportation between remote atomic-ensemble quantum memories

TL;DR

This paper demonstrates quantum teleportation between two remote atomic-ensemble quantum memories, each containing 100 million rubidium atoms, achieving high fidelity over a 150-meter fiber, advancing quantum network capabilities.

Contribution

It is the first to realize quantum teleportation between two remote macroscopic atomic ensembles, combining quantum memory and teleportation in a large-scale quantum network context.

Findings

Achieved 88% average fidelity in teleportation.

Successfully connected two atomic ensembles 150 meters apart.

First demonstration of teleportation between remote macroscopic objects.

Abstract

Quantum teleportation and quantum memory are two crucial elements for large-scale quantum networks. With the help of prior distributed entanglement as a "quantum channel", quantum teleportation provides an intriguing means to faithfully transfer quantum states among distant locations without actual transmission of the physical carriers. Quantum memory enables controlled storage and retrieval of fast-flying photonic quantum bits with stationary matter systems, which is essential to achieve the scalability required for large-scale quantum networks. Combining these two capabilities, here we realize quantum teleportation between two remote atomic-ensemble quantum memory nodes, each composed of 100 million rubidium atoms and connected by a 150-meter optical fiber. The spinwave state of one atomic ensemble is mapped to a propagating photon, and subjected to Bell-state measurements with another single photon that is entangled with the spinwave state of the other ensemble. Two-photon detection events herald the success of teleportation with an average fidelity of 88(7)%. Besides its fundamental interest as the first teleportation between two remote macroscopic objects, our technique may be useful for quantum information transfer between different nodes in quantum networks and distributed quantum computing.