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arXiv · 1911.10841

High-rate, high-fidelity entanglement of qubits across an elementary quantum network

L J Stephenson·D P Nadlinger·B C Nichol·S An·P Drmota·T G Ballance·K Thirumalai·J F Goodwin·D M Lucas·C J Ballance
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Abstract

We demonstrate remote entanglement of trapped-ion qubits via a quantum-optical fiber link with fidelity and rate approaching those of local operations. Two ${}^{88}$Sr${}^{+}$ qubits are entangled via the polarization degree of freedom of two photons which are coupled by high-numerical-aperture lenses into single-mode optical fibers and interfere on a beamsplitter. A novel geometry allows high-efficiency photon collection while maintaining unit fidelity for ion-photon entanglement. We generate remote Bell pairs with fidelity $F=0.940(5)$ at an average rate $182\,\mathrm{s}^{-1}$ (success probability $2.18\times10^{-4}$).

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L J Stephenson, D P Nadlinger, B C Nichol, S An, P Drmota, T G Ballance, K Thirumalai, J F Goodwin, D M Lucas, C J Ballance. 2020-05-13. High-rate, high-fidelity entanglement of qubits across an elementary quantum network. https://doi.org/10.1103/physrevlett.124.110501

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