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arXiv · 1906.04864

Resource-efficient and fault-tolerant topological quantum computation with hybrid entanglement of light

S. Omkar·Y. S. Teo·H. Jeong
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Abstract

We propose an all-linear-optical scheme to ballistically generate a cluster state for measurement-based topological fault-tolerant quantum computation using hybrid photonic qubits entangled in a continuous-discrete domain. Availability of near-deterministic Bell-state measurements on hybrid qubits is exploited for the purpose. In the presence of photon losses, we show that our scheme leads to a significant enhancement in both tolerable photon-loss rate and resource overheads. More specifically, we report a photon-loss threshold of $\sim3.3\times 10^{-3}$, which is higher than those of known optical schemes under a reasonable error model. Furthermore, resource overheads to achieve logical error rate of $10^{-6} (10^{-15})$ is estimated to be $\sim8.5\times10^{5} (1.7\times10^{7})$ which is significantly less by multiple orders of magnitude compared to other reported values in the literature.

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S. Omkar, Y. S. Teo, H. Jeong. 2020-07-17. Resource-efficient and fault-tolerant topological quantum computation with hybrid entanglement of light. https://doi.org/10.1103/physrevlett.125.060501

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