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arXiv · 1606.00685

Experimental demonstration of a resonator-induced phase gate in a multi-qubit circuit QED system

Hanhee Paik·A. Mezzacapo·Martin Sandberg·D. T. McClure·B. Abdo·A. D. Corcoles·O. Dial·D. F. Bogorin·B. L. T. Plourde·M. Steffen·A. W. Cross·J. M. Gambetta·Jerry M. Chow
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Abstract

The resonator-induced phase (RIP) gate is a multi-qubit entangling gate that allows a high degree of flexibility in qubit frequencies, making it attractive for quantum operations in large-scale architectures. We experimentally realize the RIP gate with four superconducting qubits in a three-dimensional (3D) circuit-quantum electrodynamics architecture, demonstrating high-fidelity controlled-Z (CZ) gates between all possible pairs of qubits from two different 4-qubit devices in pair subspaces. These qubits are arranged within a wide range of frequency detunings, up to as large as 1.8 GHz. We further show a dynamical multi-qubit refocusing scheme in order to isolate out 2-qubit interactions, and combine them to generate a four-qubit Greenberger-Horne-Zeilinger state.

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Hanhee Paik, A. Mezzacapo, Martin Sandberg, D. T. McClure, B. Abdo, A. D. Corcoles, O. Dial, D. F. Bogorin, B. L. T. Plourde, M. Steffen, A. W. Cross, J. M. Gambetta, Jerry M. Chow. 2016-06-02. Experimental demonstration of a resonator-induced phase gate in a multi-qubit circuit QED system. https://doi.org/10.1103/physrevlett.117.250502

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