arXiv:2101.11082 · Physical Review A

Error-correcting entanglement swapping using a practical logical photon encoding

Paul Hilaire, Edwin Barnes, Sophia E. Economou, Frédéric Grosshans

Published Nov 29, 2021• 25 citations

Abstract

Several emerging quantum technologies, including quantum networks, and 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.

DOI: 10.1103/physreva.104.052623

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