Pressure and isotope effect on the anisotropy of MgB$_{2}$

T. Schneider; D. Di Castro

doi:10.1103/physrevb.72.054501

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Pressure and isotope effect on the anisotropy of MgB$_{2}$

T. Schneider·D. Di Castro

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Abstract

We analyze the data for the pressure and boron isotope effect on the temperature dependence of the magnetization near $T_{c}$. Invoking the universal scaling relation for the magnetization at fixed magnetic field it is shown that the relative shift of $T_{c}$, induced by pressure or boron isotope exchange, mirrors essentially that of the anisotropy. This uncovers a novel generic property of anisotropic type II superconductors, inexistent in the isotropic case. For MgB$_{2}$ it implies that the renormalization of the Fermi surface topology due to pressure or isotope exchange is dominated by a mechanism controlling the anisotropy.

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T. Schneider, D. Di Castro. 2005-02-08. Pressure and isotope effect on the anisotropy of MgB$_{2}$. https://doi.org/10.1103/physrevb.72.054501

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