Wide field imaging of superconducting vortices using Nitrogen-Vacancy centers in diamonds

Y. Schlussel, T. Lenz, A. Waxman, P. Maletinsky, D. Budker, and R. Folman

Atom Chip Group, Ben-Gurion University of the Negev

In recent years diamond magnetometers based on the nitrogen-vacancy (NV) center have been of considerable interest for applications at the nanoscale. An interesting application which is well suited for NV centers is the study of magnetic phenomena in superconducting materials [1]. Of special interest is to provide novel insight into high Tc superconductivity, so that higher Tc materials may be realized. We employ NV centers to interrogate magnetic properties of a thin-layer yttrium barium copper oxide (YBCO) superconductor. Previously, we probed the collective properties of the superconductor [2]. Here, using wide-field fluorescence-microscopy methods and specially designed microdiamond samples, we integrate a YBCO thin-film layer, and achieve imaging without scanning of vortices in YBCO samples [3]. In this proof-of-principle work we present images of the vortices, as well as the vortex density as a function of the external magnetic field during the cooling of the superconducting sample. Next we intend to study more complex phenomena in high Tc superconductors.

[1] V.M. Acosta, L.-S. Bouchard, L.-S. Bouchard, R. Folman, T. Lenz, P. Maletinsky, D. Rohner, Y. Schlussel, L. Thiel, Color Centers in Diamond as Novel Probes of Superconductivity, JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM, (2018)

[2] A. Waxman, Y. Schlussel, D. Groswasser, V. M. Acosta, L.-S. Bouchard, D. Budker, and R. Folman,
Diamond magnetometry of superconducting thin films, PHYSICAL REVIEW B 89, 054509 (2014).

[3] Y. Schlussel, T. Lenz, P. Maletinsky, D. Rohner, Y. Bar-Haim, L. Bougas, D. Groswasser, M. Kieschnick, E. Rozenberg, L. Thiel, A. Waxman, J. Meijer, P. Maletinsky, D. Budker, R. Folman, Wide-Field Imaging of Superconductor Vortices with Electron Spins in Diamond, PHYSICAL REVIEW APPLIED 10, 034032 (2018)