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arXiv · 1704.02221

Multiqubit Greenberger-Horne-Zeilinger state generated by synthetic magnetic field in circuit QED

Wei Feng·Da-Wei Wang·Han Cai·Shi-Yao Zhu
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Abstract

We propose a scheme to generate Greenberger-Horne-Zeilinger (GHZ) state for N superconducting qubits in a circuit QED system. By sinusoidally modulating the qubit-qubit coupling, a synthetic magnetic field has been made which broken the time-reversal symmetry of the system. Directional rotation of qubit excitation can be realized in a three-qubit loop under the artificial magnetic field. Based on the special quality that the rotation of qubit excitation has different direction for single- and double-excitation loops, we can generate three-qubit GHZ state and extend this preparation method to arbitrary multiqubit GHZ state. Our analysis also shows that the scheme is robust to various operation errors and environmental noise.

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Wei Feng, Da-Wei Wang, Han Cai, Shi-Yao Zhu. 2017-04-07. Multiqubit Greenberger-Horne-Zeilinger state generated by synthetic magnetic field in circuit QED. https://arxiv.org/abs/1704.02221

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