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Spontaneous magnetic moments in YBCO thin films

F. Tafuri·J. R. Kirtley
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Abstract

We have observed spontaneous magnetic moments with random signs in c-axis oriented thin films of the high-Tc cuprate superconductor YBCO, imaged with a scanning SQUID microscope. These moments arise when the samples become superconducting, and appear to be associated with non-ferromagnetic defects in the films. In contrast with granular high-Tc samples, which also show spontaneous magnetization with random signs, these samples shield diamagnetically.

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F. Tafuri, J. R. Kirtley. 2000-05-15. Spontaneous magnetic moments in YBCO thin films. https://doi.org/10.1103/physrevb.62.13934

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