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arXiv · 1906.02992

Realization of Superadiabatic Two-qubit Gates Using Parametric Modulation in Superconducting Circuits

Ji Chu·Danyu Li·Xiaopei Yang·Shuqing Song·Zhikun Han·Zhen Yang·Yuqian Dong·Wen Zheng·Zhimin Wang·Xiangmin Yu·Dong Lan·Xinsheng Tan·Yang Yu
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Abstract

Fast robust two-qubit gate operation with low susceptibility to crosstalk are the key to scalable quantum information processing. Parametrically driven gate is inherently insensitive to crosstalk while superadiabatic control can speed up the gate without losing accuracy. We propose and experimentally implement superadiabatic two-qubit gates using parametric modulation on superconducting quantum circuits. Our results demonstrate the preservation of adiabaticity at a gate speed close to the quantum limit, in addition to robustness against control instability. We demonstrate a CZ gate with error rate of 5.8$\%$, limited largely by qubit decoherence, promising future improvement and scalable implementation.

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Ji Chu, Danyu Li, Xiaopei Yang, Shuqing Song, Zhikun Han, Zhen Yang, Yuqian Dong, Wen Zheng, Zhimin Wang, Xiangmin Yu, Dong Lan, Xinsheng Tan, Yang Yu. 2019-06-07. Realization of Superadiabatic Two-qubit Gates Using Parametric Modulation in Superconducting Circuits. https://doi.org/10.1103/physrevapplied.13.064012

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