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Reversible magnetization of MgB2 single crystals with a two-gap nature

Byeongwon Kang·Heon-Jung Kim·min-Seok Park·Kyung-Hee Kim·Sung-Ik Lee
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Abstract

We present reversible magnetization measurements on MgB2 single crystals in magnetic fields up to 2.5 T applied parallel to the crystal's c-axis. This magnetization is analyzed in terms of the Hao-Clem model, and various superconducting parameters, such as the critical fields [Hc(0) and Hc2(0)], the characteristic lengths [xi(0) and lambda(0)], and the Ginzburg-Landau parameter, kappa, are derived. The temperature dependence of the magnetic penetration depth, lambda(T), obtained from the Hao-Clem analysis could not be explained by theories assuming a single gap. Our data are well described by using a two-gap model.

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Byeongwon Kang, Heon-Jung Kim, min-Seok Park, Kyung-Hee Kim, Sung-Ik Lee. 2004-03-04. Reversible magnetization of MgB2 single crystals with a two-gap nature. https://doi.org/10.1103/physrevb.69.144514

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