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Quantum tunneling of vortices in a MgB$_2$ superconductor

Y. Z. Zhang·R. Deltour·H. H. Wen·C. Q. Jin·Y. M. Ni·S. L Jia·G. C. Che·Z. X. Zhao
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Abstract

Magnetic relaxation in a MgB$_2$ superconductor was measured. The temperature dependence of the normalized relaxation rate was determined for three different magnetic fields. By extrapolating these rates to T=0 K, we find that these extrapolations do not approach zero, indicating quantum tunneling of vortices in the superconductor. A quantum correction of the relaxation rate, followed by the correction of the magnetic moment, is proposed. Using the quantum correction, we find that $U_0$ increases with decreasing temperature and approaches a maximum at T=0.

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Y. Z. Zhang, R. Deltour, H. H. Wen, C. Q. Jin, Y. M. Ni, S. L Jia, G. C. Che, Z. X. Zhao. 2002-12-05. Quantum tunneling of vortices in a MgB$_2$ superconductor. https://doi.org/10.1063/1.1530735

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