Critical Field of MGB2 : Crossover from Clean to Dirty Regimes

Abstract

We have studied the upper critical field, Bc2, in poly-crystalline MgB2 samples in which disorder was varied in a controlled way to carry selectively p and s bands from clean to dirty limit. We have found that the clean regime survives when p bands are dirty and s bands are midway between clean and dirty. In this framework we can explain the anomalous behaviour of Al doped samples, in which Bc2 decreases as doping increases.

arXiv comment11 pages, 2 figures

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Cited by in corpus (15)

• Limits of the upper critical field in dirty two-gap superconductors
• Effects of neutron irradiation on polycrystalline Mg11B2
• The different development of the anisotropic upper critical field in MgB2 by aluminum and carbon doping
• Correlated enhancement of Hc2 and Jc in carbon nanotube-doped MgB2
• Critical Field of Al-Doped MgB2 Samples: Correlation with the Suppression of Sigma-Band Gap
• Magnetic field dependence of the density of states in the multiband superconductor $\beta$-Bi${}_2$Pd
• Systematic study of disorder induced by neutron irradiation in MgB2 thin films
• Magnetoresistivity in MgB2 as a probe of disorder in p- and s-bands
• Upper Critical Fields up to 60T in Dirty Magnesium Diboride Thin Films
• Clean and Dirty Superconductivity in Pure, Al doped, and Neutron Irradiated MgB2: a Far-Infrared Study
• Theory of vortices in hybridized ballistic/diffusive-band superconductors
• Ballistic and diffusive: theory of vortices in the two-band superconductor MgB2
• Reaction method control of impurity scattering in C-doped MgB2, proving the role of defects besides C substitution level
• Band filling and disorder effects on the normal state thermoelectric behavior in MgB2
• Carrier Transport in Magnesium Diboride: Role of Nano-inclusions