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arXiv · 1708.07506

Dendritic flux avalanches in a superconducting MgB2 tape

Thomas Qureishy·Carlos Laliena·Elena Martínez·Atle Jorstad Qviller·Jørn Inge Vestgården·Tom Henning Johansen·Rafael Navarro·Pavlo Mikheenko
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Abstract

MgB2 tapes with high critical current have a significant technological potential, but can experience operational breakdown due to thermomagnetic instability. Using magneto-optical imaging the spatial structure of the thermomagnetic avalanches has been resolved, and the reproducibility and thresholds for their appearance have been determined. By combining magneto-optical imaging with magnetic moment measurements, it is found that avalanches appear in a range between 1.7 mT and 2.5 T. Avalanches appearing at low fields are small intrusions at the tape's edge and non-detectable in measurements of magnetic moment. Larger avalanches have dendritic structures.

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Thomas Qureishy, Carlos Laliena, Elena Martínez, Atle Jorstad Qviller, Jørn Inge Vestgården, Tom Henning Johansen, Rafael Navarro, Pavlo Mikheenko. 2017-08-24. Dendritic flux avalanches in a superconducting MgB2 tape. https://doi.org/10.1088/1361-6668/aa9244

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