Demonstration of long-range correlations via susceptibility measurements in a one-dimensional superconducting Josephson spin chain

Journal Article · 17 July 2022 · npj Quantum Information

DOI: https://doi.org/10.1038/s41534-022-00590-8 · OSTI ID:1876672

Tennant, D. M. ; Dai, X. ; Martinez, A. J.; Trappen, R.; Melanson, D.; Yurtalan, M. A.; Tang, Y. ; Bedkihal, S.; Yang, R.; Novikov, S. ; Grover, J. A.; Disseler, S. M.; Basham, J. I. ; Das, R.; Kim, D. K.; Melville, A. J.; Niedzielski, B. M.; Weber, S. J. ; Yoder, J. L.; Kerman, A. J. ; Mozgunov, E.; Lidar, D. A. ; Lupascu, A.

Abstract Spin chains have long been considered an effective medium for long-range interactions, entanglement generation, and quantum state transfer. In this work, we explore the properties of a spin chain implemented with superconducting flux circuits, designed to act as a connectivity medium between two superconducting qubits. The susceptibility of the chain is probed and shown to support long-range, cross-chain correlations. In addition, interactions between the two end qubits, mediated by the coupler chain, are demonstrated. This work has direct applicability in near term quantum annealing processors as a means of generating long-range, coherent coupling between qubits.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: US Army Research Office (ARO); USDOE; USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC52-07NA27344
• OSTI ID: 1876672
• Report Number(s): LLNL-JRNL-827623; 85; PII: 590
• Journal Information: npj Quantum Information, Journal Name: npj Quantum Information Journal Issue: 1 Vol. 8; ISSN 2056-6387
• Publisher: Nature Publishing GroupCopyright Statement
• Country of Publication: United Kingdom
• Language: English