Synthesis of antisymmetric spin exchange interaction and chiral spin clusters in superconducting circuits

ABSTRACT According to quantum mechanics, chiral states cannot be non-degenerate eingenstates of a parity-conserving Hamiltonian. This is in contradiction to the existence of chiral

molecules—a fact known as as the Hund paradox1. The origin of molecular and biological chirality is conjectured to be related to parity-breaking interactions2,3 or environmental

decoherence4, but a quantum superposition of two chiral molecular states with distinctive optical activities has never been observed5. To make progress in addressing these questions, it

would be helpful to construct an artificial quantum system that breaks the parity symmetry and that can be prepared in a superposition of two chiral states. Here we report the synthesis of

the parity-breaking antisymmetric spin exchange interaction in all-to-all connected superconducting circuits, which allows us to show various chiral spin dynamics in up to five-spin

clusters. We also demonstrate the entanglement of up to five qubits in Greenberger–Horne–Zeilinger states based on a three-spin chiral logic gate. Our results are a step towards quantum

simulation of magnetism with antisymmetric spin exhange interaction and quantum computation with chiral spin states. Access through your institution Buy or subscribe This is a preview of

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* Log in * Learn about institutional subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS CHIRAL SPINTRONICS Article 08 April 2021 GIANT SPIN

POLARIZATION AND A PAIR OF ANTIPARALLEL SPINS IN A CHIRAL SUPERCONDUCTOR Article 18 January 2023 CHIRAL MOLECULAR INTERCALATION SUPERLATTICES Article 29 June 2022 DATA AVAILABILITY The data

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Separability criteria for genuine multiparticle entanglement. _New J. Phys._ 12, 053002 (2010). Article  Google Scholar  Download references ACKNOWLEDGEMENTS The authors thank W. Liu, Q. Guo

and K. Huang for technical support. This research was supported by the National Key Research and Development Program of China (grants nos. 2018YFA0307200, 2017YFA0304202 and

2016YFA0300601), the National Natural Science Foundations of China (grants nos. 11434008, 11574380, 11725419 and 11874322) and the Fundamental Research Funds for the Central Universities of

China (grant no. 2016XZZX002-01). D.W.W. was also supported by the key research programme of the Chinese Academy of Sciences (grant no. XDPB08-3). M.O.S. was supported by the Air Force

Office of Scientific Research (award no. FA9550-18-1-0141), the Office of Naval Research (award no. N00014-16-1-3054) and the Robert A. Welch Foundation (grant no. A-1261). Devices were made

at the Nanofabrication Facilities at the Institute of Physics in Beijing, the University of Science and Technology of China in Hefei and the National Center for Nanoscience and Technology

in Beijing. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Interdisciplinary Center for Quantum Information, Department of Physics and State Key Laboratory of Modern Optical Instrumentation,

Zhejiang University, Hangzhou, Zhejiang, China Da-Wei Wang, Chao Song, Wei Feng, Han Cai, Da Xu, H. Wang & Shi-Yao Zhu * Institute of Quantum Science and Engineering, Texas A&M

University, College Station, TX, USA Da-Wei Wang & Marlan O. Scully * CAS Center of Excellence in Topological Quantum Computation, Beijing, China Da-Wei Wang & Dongning Zheng *

Beijing Computational Science Research Center, Beijing, China Wei Feng * Institute of Physics, Chinese Academy of Sciences, Beijing, China Hui Deng, Hekang Li & Dongning Zheng * School

of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China Hekang Li & Dongning Zheng * Synergetic Innovation Center of Quantum Information and Quantum Physics,

University of Science and Technology of China, Hefei, Anhui, China Xiaobo Zhu & Shi-Yao Zhu Authors * Da-Wei Wang View author publications You can also search for this author inPubMed 

Google Scholar * Chao Song View author publications You can also search for this author inPubMed Google Scholar * Wei Feng View author publications You can also search for this author

inPubMed Google Scholar * Han Cai View author publications You can also search for this author inPubMed Google Scholar * Da Xu View author publications You can also search for this author

inPubMed Google Scholar * Hui Deng View author publications You can also search for this author inPubMed Google Scholar * Hekang Li View author publications You can also search for this

author inPubMed Google Scholar * Dongning Zheng View author publications You can also search for this author inPubMed Google Scholar * Xiaobo Zhu View author publications You can also search

for this author inPubMed Google Scholar * H. Wang View author publications You can also search for this author inPubMed Google Scholar * Shi-Yao Zhu View author publications You can also

search for this author inPubMed Google Scholar * Marlan O. Scully View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS D.W.W. conceived the idea

and formulated the theory. D.W.W. and H.W. planned the project. C.S. performed the experiments. W.F., H.C. and C.S. carried out the simulation and analysed the data. H.D., H.L., D.Z. and

X.Z. fabricated the sample with designs and support from H.W.’s group. D.X. provided technical support. D.W.W., W.F. and H.W. wrote the paper and S.Y.Z. and M.O.S. made comments.

CORRESPONDING AUTHORS Correspondence to Da-Wei Wang, Xiaobo Zhu or H. Wang. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. ADDITIONAL INFORMATION

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Supplementary methods and figures RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Wang, DW., Song, C., Feng, W. _et al._ Synthesis of antisymmetric spin

exchange interaction and chiral spin clusters in superconducting circuits. _Nat. Phys._ 15, 382–386 (2019). https://doi.org/10.1038/s41567-018-0400-9 Download citation * Received: 22 January

2018 * Accepted: 06 December 2018 * Published: 21 January 2019 * Issue Date: April 2019 * DOI: https://doi.org/10.1038/s41567-018-0400-9 SHARE THIS ARTICLE Anyone you share the following

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