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arXiv · 2112.11304

High-fidelity CNOT gate for spin qubits with asymmetric driving using virtual gates

Irina Heinz·Guido Burkard
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Abstract

Recent experiments have demonstrated two-qubit fidelities above 99%, however, theoretically, the fidelity of CNOT operations is limited by off-resonant driving described by off-diagonal terms in the system Hamiltonian. Here we investigate these off-diagonal contributions and we propose a fidelity improvement of several orders of magnitude by using asymmetric driving. Therefore, we provide a description of an ac virtual gate based on a simple capacitance model which not only enables a high fidelity CNOT but also crosstalk reduction when scaling up spin qubit devices to larger arrays.

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Irina Heinz, Guido Burkard. 2021-12-21. High-fidelity CNOT gate for spin qubits with asymmetric driving using virtual gates. https://doi.org/10.1103/physrevb.105.l121402

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