Qubit teleportation between non-neighbouring nodes in a quantum network

Matteo Pompili (left) and Sophie Hermans (right) work on one of the quantum network nodes, where mirrors and filters guide the laser beams to the diamond chip. Credit: Marieke de Lorijn for QuTech.

Abstract

Future quantum internet applications will derive their power from the ability to share quantum information across the network. Quantum teleportation allows for the reliable transfer of quantum information between distant nodes, even in the presence of highly lossy network connections. Although many experimental demonstrations have been performed on different quantum network platforms, moving beyond directly connected nodes has, so far, been hindered by the demanding requirements on the pre-shared remote entanglement, joint qubit readout and coherence times. Here we realize quantum teleportation between remote, non-neighbouring nodes in a quantum network. The network uses three optically connected nodes based on solid-state spin qubits. The teleporter is prepared by establishing remote entanglement on the two links, followed by entanglement swapping on the middle node and storage in a memory qubit. We demonstrate that, once successful preparation of the teleporter is heralded, arbitrary qubit states can be teleported with fidelity above the classical bound, even with unit efficiency. These results are enabled by key innovations in the qubit readout procedure, active memory qubit protection during entanglement generation and tailored heralding that reduces remote entanglement infidelities. Our work demonstrates a prime building block for future quantum networks and opens the door to exploring teleportation-based multi-node protocols and applications.

Publication
Nature
Matteo Pompili
Matteo Pompili
Amazon Postdoctoral Scientist. Experimental Quantum Physicist, Research Software Developer

I am an experimental quantum physicist and a research software developer. My research focuses on quantum networks. I am currently a postdoctoral scientist at the AWS Center for Quantum Networking. During my PhD I built the first multinode quantum network, and demonstrated entanglement delivery using a quantum network stack.