Modern Magnetic Systems Article 2014

Detecting magnetic flux distributions in superconductors with polarized x-rays

Superstuff

The magnetic flux distribution arising from a high-Tc superconductor is detected and visualized using polarized x rays. Therefore, we introduce a sensor layer, namely, an amorphous, soft-magnetic Co40Fe40B20 cover layer, providing a large x-ray magnetic circular dichroism (XMCD). Temperature-dependent XMCD spectroscopy on the magnetic layer has been performed. Exploiting the temperature dependence of the critical current density of the superconductor we find a quantitative correlation between the XMCD signal and the in-plane stray field of the superconductor. Magneto-optical Kerr effect experiments on the sensor layer can simulate the stray field of the superconductor and hence verify the correlation. We show that the XMCD contrast in the sensor layer corresponds to the in-plane magnetic flux distribution of the superconductor and can hence be used to image magnetic structures in superconductors.

Author(s): Stahl, C. and Audehm, P. and Gräfe, J. and Ruoß, Stephen and Weigand, M. and Schmidt, M. and Treiber, S. and Bechtel, M. and Goering, E. and Schütz, G. and Albrecht, J.
Journal: {Physical Review B}
Volume: 90
Number (issue): 10
Year: 2014
Publisher: American Physical Society
Bibtex Type: Article (article)
DOI: 10.1103/PhysRevB.90.104515
Address: Woodbury, NY
Electronic Archiving: grant_archive
Language: eng

BibTex

@article{escidoc:0174,
  title = {{Detecting magnetic flux distributions in superconductors with polarized x-rays}},
  journal = {{Physical Review B}},
  abstract = {The magnetic flux distribution arising from a high-Tc superconductor is detected and visualized using polarized x rays. Therefore, we introduce a sensor layer, namely, an amorphous, soft-magnetic Co40Fe40B20 cover layer, providing a large x-ray magnetic circular dichroism (XMCD). Temperature-dependent XMCD spectroscopy on the magnetic layer has been performed. Exploiting the temperature dependence of the critical current density of the superconductor we find a quantitative correlation between the XMCD signal and the in-plane stray field of the superconductor. Magneto-optical Kerr effect experiments on the sensor layer can simulate the stray field of the superconductor and hence verify the correlation. We show that the XMCD contrast in the sensor layer corresponds to the in-plane magnetic flux distribution of the superconductor and can hence be used to image magnetic structures in superconductors.},
  volume = {90},
  number = {10},
  publisher = {American Physical Society},
  address = {Woodbury, NY},
  year = {2014},
  slug = {escidoc-0174},
  author = {Stahl, C. and Audehm, P. and Gr\"afe, J. and Ruo\ss, Stephen and Weigand, M. and Schmidt, M. and Treiber, S. and Bechtel, M. and Goering, E. and Sch\"utz, G. and Albrecht, J.}
}