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Decrease of Ac Losses in High Tc Superconducting Tapes by Application of a DC Current

Benoit des Ligneris·Marcel Aubin·Julian Cave·When Zhu·Patricia Dolez
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Abstract

The ac losses in a silver-gold alloy sheathed Bi-2223 tape were measured by the null calorimetric method while a dc current was superimposed onto the ac current. As expected through computer simulations, a Clem valley was observed for the larger ac currents. A reduction of ac losses of approximately 50% at the valley minimum is observed in accord with the calculations. At lower ac currents, the data fit the calculated behavior with a single parameter, a Meissner current of 21.8 A. It is shown that a surface barrier current is incompatible with the data.

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Benoit des Ligneris, Marcel Aubin, Julian Cave, When Zhu, Patricia Dolez. 1999-07-20. Decrease of Ac Losses in High Tc Superconducting Tapes by Application of a DC Current. https://arxiv.org/abs/cond-mat/9907271

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