Hybrid entanglement of three quantum memories with three photons

TL;DR

This paper demonstrates the creation of hybrid entanglement between three photons and three quantum memories, advancing quantum network capabilities by entangling multiple nodes and photons simultaneously.

Contribution

The experiment achieves the largest hybrid memory-photon entanglement involving three nodes, surpassing previous two-node setups, and introduces a scalable approach for complex quantum networks.

Findings

Successfully entangled three quantum memories with three photons.

Achieved high overall efficiency in photon-memory entanglement.

Demonstrated heralded entanglement of multiple quantum memories.

Abstract

Quantum network has significant applications both practically and fundamentally. A hybrid architecture with photons and stationary nodes is highly promising. So far, experimental realizations are limited to two nodes with two photons. Going beyond state of the art by entangling many photons with many quantum nodes is highly appreciated. Here, we report an experiment realizing hybrid entanglement between three photons and three atomic-ensemble quantum memories. We make use of three similar setups, in each of which one pair of photon-memory entanglement with high overall efficiency is created via cavity enhancement. Through three-photon interference, the three quantum memories get entangled with the three photons. Via measuring the photons and applying feedforward, we heraldedly entangle the three memories. Our work demonstrates the largest size of hybrid memory-photon entanglement, which may be employed as a build block to construct larger and complex quantum network.