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arXiv · 1810.04182

Suppression of Qubit Crosstalk in a Tunable Coupling Superconducting Circuit

Pranav S. Mundada·Gengyan Zhang·Thomas Hazard·Andrew A. Houck
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Abstract

Parasitic crosstalk in superconducting quantum devices is a leading limitation for quantum gates. We demonstrate the suppression of static ZZ crosstalk in a two-qubit, two-coupler superconducting circuit, where the frequency of a tunable coupler can be adjusted such that the ZZ interaction from each coupler destructively interfere. We verify the crosstalk elimination with simultaneous randomized benchmarking, and use a parametrically activated iSWAP interaction to achieve a Bell state preparation fidelity of 98.5% and a $\sqrt{\textrm{iSWAP}}$ gate fidelity of 94.8% obtained via quantum process tomography.

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Pranav S. Mundada, Gengyan Zhang, Thomas Hazard, Andrew A. Houck. 2019-05-31. Suppression of Qubit Crosstalk in a Tunable Coupling Superconducting Circuit. https://doi.org/10.1103/physrevapplied.12.054023

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