Irreversibility line of the MgB$_{2}$ superconductor

Y. Z. Zhang; R. Deltour; H. H. Wen; J. F. de Marneffe; H. Chen; S. F. Wang; S. Y. Dai; Y. L. Zhou; Q. Li; A. G. M. Jansen; P. Wyder; Z. X. Zhao

arXiv · cond-mat/0110312

Irreversibility line of the MgB$_{2}$ superconductor

Y. Z. Zhang·R. Deltour·H. H. Wen·J. F. de Marneffe·H. Chen·S. F. Wang·S. Y. Dai·Y. L. Zhou·Q. Li·A. G. M. Jansen·P. Wyder·Z. X. Zhao

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Abstract

Magneto-resistivity of a c-axis oriented MgB$_{2}$ thin film was studied in perpendicular and parallel magnetic fields up to $\sim $23 T with temperatures down to 0.38 K. Resistive critical magnetic fields were determined. Large separations between irreversibility lines and upper critical magnetic fields are observed. An effective quantum parameter as a function of temperature is proposed to explain the separations under the theoretical framework of quantum fluctuations, in good agreement with our experimental and previously published experimental data.

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Y. Z. Zhang, R. Deltour, H. H. Wen, J. F. de Marneffe, H. Chen, S. F. Wang, S. Y. Dai, Y. L. Zhou, Q. Li, A. G. M. Jansen, P. Wyder, Z. X. Zhao. 2002-03-05. Irreversibility line of the MgB$_{2}$ superconductor. https://arxiv.org/abs/cond-mat/0110312

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