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arXiv · 1712.05261

Synthesis of antisymmetric spin exchange interaction and entanglement generation with chiral spin states in a superconducting circuit

Da-Wei Wang·Chao Song·Wei Feng·Han Cai·Da Xu·Hui Deng·Dongning Zheng·Xiaobo Zhu·H. Wang·Shiyao Zhu·Marlan O. Scully
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Abstract

We have synthesized the anti-symmetric spin exchange interaction (ASI), which is also called the Dzyaloshinskii-Moriya interaction, in a superconducting circuit containing five superconducting qubits connected to a bus resonator, by periodically modulating the transition frequencies of the qubits with different modulation phases. This allows us to show the chiral spin dynamics in three-, four- and five-spin clusters. We also demonstrate a three-spin chiral logic gate and entangle up to five qubits in Greenberger-Horne-Zeilinger states. Our results pave the way for quantum simulation of magnetism with ASI and quantum computation with chiral spin states.

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Da-Wei Wang, Chao Song, Wei Feng, Han Cai, Da Xu, Hui Deng, Dongning Zheng, Xiaobo Zhu, H. Wang, Shiyao Zhu, Marlan O. Scully. 2017-12-14. Synthesis of antisymmetric spin exchange interaction and entanglement generation with chiral spin states in a superconducting circuit. https://doi.org/10.1038/s41567-018-0400-9

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