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

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.

20 pages, 1 table, 4 figures, will be published in Phys. Rev. B

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Cited by in corpus (4)

• Properties of the superconducting state in a two-band model
• Mixed-State Thermodynamics of Superconductors with Moderately Large Paramagnetic Effects
• Reversible magnetization measurement of the anisotropy of the London penetration depth in MgB2 single crystals
• Strong phase coherence and vortex matter in a fractal system with proximity-induced superconductivity