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arXiv · 1811.08096

Experimental realization of a fast controlled-Z gate via a shortcut-to-adiabaticity

Tenghui Wang·Zhenxing Zhang·Liang Xiang·Zhilong Jia·Peng Duan·Zhiwen Zong·Zhenhai Sun·Zhangjingzi Dong·Jianlan Wu·Yi Yin·Guoping Guo
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Abstract

For a frequency-tunable two-qubit system, a controlled-Z (CZ) gate can be realized by adiabatically driving the qubit system through an avoided level crossing between an auxiliary state and computational levels. Here, we theoretically propose a fast CZ gate using a shortcut-to-adiabaticity (STA). Experimentally, the STA CZ gate is implemented with a 52 ns control pulse for two coupled superconducting Xmon qubits. Measured fidelity of the STA CZ gate is higher than 96.0%, in both quantum process tomography and randomized benchmarking. The protocol allows a flexible design of the evolution time and control waveform. We suggest that this `fast adiabatic' CZ gate can be directly applied to other multi-qubit quantum systems.

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Tenghui Wang, Zhenxing Zhang, Liang Xiang, Zhilong Jia, Peng Duan, Zhiwen Zong, Zhenhai Sun, Zhangjingzi Dong, Jianlan Wu, Yi Yin, Guoping Guo. 2018-11-20. Experimental realization of a fast controlled-Z gate via a shortcut-to-adiabaticity. https://doi.org/10.1103/physrevapplied.11.034030

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