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Suppression of Unwanted $ZZ$ Interactions in a Hybrid Two-Qubit System

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 نشر من قبل Jaseung Ku
 تاريخ النشر 2020
  مجال البحث فيزياء
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Mitigating crosstalk errors, whether classical or quantum mechanical, is critically important for achieving high-fidelity entangling gates in multi-qubit circuits. For weakly anharmonic superconducting qubits, unwanted $ZZ$ interactions can be suppressed by combining qubits with opposite anharmonicity. We present experimental measurements and theoretical modeling of two-qubit gate error for gates based on the cross resonance interaction between a capacitively shunted flux qubit and a transmon and demonstrate the elimination of the $ZZ$ interaction.



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