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arXiv:2304.01024 · Applied Physics Letters

Wide-field quantitative magnetic imaging of superconducting vortices using perfectly aligned quantum sensors

Shunsuke Nishimura, Taku Kobayashi, Daichi Sasaki, Takeyuki Tsuji, Takayuki Iwasaki, Mutsuko Hatano, Kento Sasaki, Kensuke Kobayashi

Published Sep 11, 2023• 16 citations
arXivHTMLPDF

Abstract

Various techniques have been applied to visualize superconducting vortices, providing clues to their electromagnetic response. Here, we present a wide-field, quantitative imaging of the stray field of the vortices in a superconducting thin film using perfectly aligned diamond quantum sensors. Our analysis, which mitigates the influence of the sensor inhomogeneities, visualizes the magnetic flux of single vortices in YBa2Cu3O7−δ with an accuracy of ±10%. The obtained vortex shape is consistent with the theoretical model, and penetration depth and its temperature dependence agree with previous studies, proving our technique's accuracy and broad applicability. This wide-field imaging, which in principle works even under extreme conditions, allows the characterization of various superconductors.

DOI
10.1063/5.0169521

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