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arXiv · 2105.04338

Quantum Teleportation between Remote Qubit Memories with Only a Single Photon as a Resource

Stefan Langenfeld·Stephan Welte·Lukas Hartung·Severin Daiss·Philip Thomas·Olivier Morin·Emanuele Distante·Gerhard Rempe
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Abstract

Quantum teleportation enables the deterministic exchange of qubits via lossy channels. While it is commonly believed that unconditional teleportation requires a preshared entangled qubit pair, here we demonstrate a protocol that is in principle unconditional and requires only a single photon as an ex-ante prepared resource. The photon successively interacts, first, with the receiver and then with the sender qubit memory. Its detection, followed by classical communication, heralds a successful teleportation. We teleport six mutually unbiased qubit states with average fidelity $\overline{\text{F}}=(88.3\pm1.3)\%$ at a rate of $6\,\mathrm{Hz}$ over $60\,\mathrm{m}$.

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Stefan Langenfeld, Stephan Welte, Lukas Hartung, Severin Daiss, Philip Thomas, Olivier Morin, Emanuele Distante, Gerhard Rempe. 2021-05-10. Quantum Teleportation between Remote Qubit Memories with Only a Single Photon as a Resource. https://doi.org/10.1103/physrevlett.126.130502

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