Abstract
We report on imaging magnetic flux distributions in a multilayered superconductor integrated circuit which emerge during magnetization and after field cooling of the circuit in the DC magnetic field. The obtained complicated field maps expose the flux propagation across the patterned superconducting ground planes sandwiching layers with Josephson junction-based logic cells, fine wire grid around the functional units, and multiple superconducting fill structures located in different inner layers. The observed intricate flux distributions are explained by specific patterns of Meissner screening currents and superconducting critical currents in different mutually interacting parts of the integrated circuit. Our results provide important insights into possible ways of improving the protection of superconductor integrated circuits from magnetic fields and their resilience against flux trapping.
Data availability
The data that support the findings of this study are available upon request from the authors.
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Acknowledgements
We are thankful to Dr. Rory Perkins for his interest in and support of this work. We are also grateful to Prof. Vasili Semenov for the original design of the shift registers, and to Drs. Ravi Rastogi and David Kim for overseeing the circuits fabrication runs.
Funding
The research by TR, AG, BJ, and VVV was sponsored by the Army Research Office under Grant No. W911NF-24-1-0145. The work at MIT Lincoln Laboratory was supported under Air Force Contract No. FA8702-15-D-0001 or FA8702-25-D-B002. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Army Research Office and the Air Force or the U.S. Government. Delivered to the U.S. Government with Unlimited Rights, as defined in DFARS Part 252.227–7013 or 7014 (Feb 2014). Notwithstanding any copyright notice, U.S. Government rights in this work are defined by DFARS 252.227–7013 or DFARS 252.227–7014 as detailed above. Use of this work other than as specifically authorized by the U.S. Government may violate any copyrights that exist in this work. The U.S. Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation herein.
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TR- major imaging experiments and discussion of results; AG- recovery of the sample structure from gds files and discussion of results; BJ-analysis and discussion of results, writing the paper; JM -circuit design discussion of results; ST -circuit design, discussion of results and writing the paper; VVV – magneto-optical imaging, analysis of results and writing the paper.
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Ren, T., Glatz, A., Jankó, B. et al. Magnetic flux imaging in a 3D superconductor integrated circuit. Sci Rep (2026). https://doi.org/10.1038/s41598-026-40711-3
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DOI: https://doi.org/10.1038/s41598-026-40711-3
