Investigation of the critical state of sputtered YBa2Cu3O7−x thin films using a Hall probe

doi:10.1016/0921-4534(92)90124-U

Physica C: Superconductivity

Volume 201, Issues 1–2, 10 October 1992, Pages 197-201

https://doi.org/10.1016/0921-4534(92)90124-U Get rights and content

Abstract

The critical state of DC-magnetron sputtered YBa₂Cu₃O_7−x (YBCO) thin films with critical temperatures of 90 K and critical current densities well beyond 10⁶A/cm² was investigated after magnetization with a magnetic field of 0.14 T. The sample surface of the square-shaped YBCO films was scanned using a Hall probe and the remanent axial magnetic field in the critical state was measured at a distance of z=0.5 mm above the sample. A comparison with theoretical calculations of the axial magnetic field resulted in a good qualitative agreement of experiment and calculation. This indicates that the samples were homogeneous. Additionally, a mapping of the critical state yields a more reliable j_c-value compared to a single local measurement without any information about the homogeneity of the sample.

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A contribution to the analysis of the current-density distribution in elongated hard type-II superconductors with rectangular cross-section
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¹: Experimental work done at Siemens Research Laboratories, Erlangen, Germany.

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Investigation of the critical state of sputtered YBa2Cu3O7−x thin films using a Hall probe

Abstract

Physica C

Physica C

Physica C

Physica C

Physica C

Jpn. J. Appl. Phys.

Investigation of the critical state of sputtered YBa₂Cu₃O_7−x thin films using a Hall probe