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arXiv · 1902.07649

Optimized cavity-mediated dispersive two-qubit gates between spin qubits

M. Benito·J. R. Petta·Guido Burkard
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Abstract

The recent realization of a coherent interface between a single electron in a silicon quantum dot and a single photon trapped in a superconducting cavity opens the way for implementing photon-mediated two-qubit entangling gates. In order to couple a spin to the cavity electric field some type of spin-charge hybridization is needed, which impacts spin control and coherence. In this work we propose a cavity-mediated two-qubit gate and calculate cavity-mediated entangling gate fidelities in the dispersive regime, accounting for errors due to the spin-charge hybridization, as well as photon- and phonon-induced decays. By optimizing the degree of spin-charge hybridization, we show that two-qubit gates mediated by cavity photons are capable of reaching fidelities exceeding 90% in present-day device architectures. High iSWAP gate fidelities are achievable even in the presence of charge noise at the level of $2\,μ\text{eV}$.

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M. Benito, J. R. Petta, Guido Burkard. 2019-02-20. Optimized cavity-mediated dispersive two-qubit gates between spin qubits. https://doi.org/10.1103/physrevb.100.081412

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