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Substitution induced pinning in MgB_2 superconductor doped with SiC nano-particles

S. X. Dou·A. V. Pan·S. Zhou·M. Ionescu·H. K. Liu·P. R. Munroe
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Abstract

By doping MgB_2 superconductor with SiC nano-particles, we have successfully introduced pinning sites directly into the crystal lattice of MgB_2 grains (intra-grain pinning). It became possible due to the combination of counter-balanced Si and C co-substitution for B, leading to a large number of intra-granular dislocations and the dispersed nano-size impurities induced by the substitution. The magnetic field dependence of the critical current density was significantly improved in a wide temperature range, whereas the transition temperature in the sample MgB_2(SiC)_x having x = 0.34, the highest doping level prepared, dropped only by 2.6 K.

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S. X. Dou, A. V. Pan, S. Zhou, M. Ionescu, H. K. Liu, P. R. Munroe. 2002-06-24. Substitution induced pinning in MgB_2 superconductor doped with SiC nano-particles. https://doi.org/10.1088/0953-2048%2F15%2F11%2F317

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