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Magnetization studies on superconducting MgB$_2$ - lower and upper critical fields and critical current density

Amish G. Joshi·C. G. S. Pillai·P. Raj·S. K. Malik
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Abstract

Magnetization studies have been carried out on superconducting MgB$_2$ (T$_c$=37K) in the temperature range of 2-50K and in magnetic field up to 5 Tesla. From these measurements, values of the lower critical field H$_c1$(0), upper critical field H$_c2$(0) at zero K are estimated to be ~300 Oe and ~12.5 Tesla, respectively, which yield a value of ~26 for the Ginzburg-Landau parameter, k. Magnetization hysteresis loops have been obtained at various temperatures from which the magnetization critical current density is estimated using Bean's critical state model.

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Amish G. Joshi, C. G. S. Pillai, P. Raj, S. K. Malik. 2001-03-14. Magnetization studies on superconducting MgB$_2$ - lower and upper critical fields and critical current density. https://doi.org/10.1016/s0038-1098(01)00149-1

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