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arXiv · cond-mat/0212383

Anisotropy parameters of superconducting MgB$_2$

V. G. Kogan·S. L. Bud'ko
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Abstract

Data on macroscopic superconducting anisotropy of MgB$_2$ are reviewed. The data are described within a weak coupling two-gaps anisotropic s-wave model of superconductivity. The calculated ratio of the upper critical fields $γ_H=H_{c2,ab}/H_{c2,c}$ increases with decreasing temperature in agreement with available data, whereas the calculated ratio of London penetration depths $γ_λ=λ_c/λ_{ab}$ decreases to reach $\approx 1.1$ at T=0. Possible macroscopic consequences of $γ_λ\neγ_H$ are discussed.

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V. G. Kogan, S. L. Bud'ko. 2002-12-16. Anisotropy parameters of superconducting MgB$_2$. https://doi.org/10.1016/s0921-4534(02)02293-1

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