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arXiv · 1808.07638

Logical measurement-based quantum computation in circuit-QED

Jaewoo Joo·Chang-Woo Lee·Shingo Kono·Jaewan Kim
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Abstract

We propose a new scheme of measurement-based quantum computation (MBQC) using an error-correcting code against photon-loss in circuit quantum electrodynamics. We describe a specific protocol of logical single-qubit gates given by sequential cavity measurements for logical MBQC and a generalised Schr\"odinger cat state is used for a continuous-variable (CV) logical qubit captured in a microwave cavity. It is assumed that a three CV-qudit entangled state is initially prepared in three jointed cavities and the microwave qudit states are individually controlled, operated, and measured through a readout resonator coupled with an ancillary superconducting qubit. We then examine a practical approach of how to create the CV-qudit cluster state via a cross-Kerr interaction induced by intermediary superconducting qubits between neighbouring cavities under the Jaynes-Cummings Hamiltonian. This approach could be scalable for building 2D logical cluster states and therefore will pave a new pathway of logical MBQC in superconducting circuits toward fault-tolerant quantum computing.

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Jaewoo Joo, Chang-Woo Lee, Shingo Kono, Jaewan Kim. 2018-08-23. Logical measurement-based quantum computation in circuit-QED. https://doi.org/10.1038/s41598-019-52866-3

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