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arXiv · 2101.11082

Error-correcting entanglement swapping using a practical logical photon encoding

Paul Hilaire·Edwin Barnes·Sophia E. Economou·Frédéric Grosshans
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Abstract

Several emerging quantum technologies, including quantum networks, modular and fusion-based quantum computing, rely crucially on the ability to perform photonic Bell state measurements. Therefore, photon losses and the 50\% success probablity upper bound of Bell state measurements pose a critical limitation to photonic quantum technologies. Here, we develop protocols that overcome these two key challenges through logical encoding of photonic qubits. Our approach uses a tree graph state logical encoding, which can be produced deterministically with a few quantum emitters, and achieves near-deterministic logical photonic Bell state measurements while also protecting against errors including photon losses, with a record loss-tolerance threshold.

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Paul Hilaire, Edwin Barnes, Sophia E. Economou, Frédéric Grosshans. 2021-01-26. Error-correcting entanglement swapping using a practical logical photon encoding. https://doi.org/10.1103/physreva.104.052623

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