Free energy and torque for superconductors with different anisotropies of H(c2) and lambda.

Abstract

The free energy is evaluated for a uniaxial superconductor with the anisotropy of the upper critical field, gamma(H)=H(c2,a)/H(c2,c), different from the anisotropy of the penetration depth gamma(lambda)=lambda(c)/lambda(a). With increasing difference between gamma(H) and gamma(lambda), the equilibrium orientation of the crystal relative to the applied field may shift from theta=pi/2 (theta is the angle between the field and the c axis) to lower angles and reach theta=0 for large enough gamma(H). These effects are expected to take place in MgB2.

Cite this paper

@article{Kogan2002FreeEA, title={Free energy and torque for superconductors with different anisotropies of H(c2) and lambda.}, author={Vladimir G. Kogan}, journal={Physical review letters}, year={2002}, volume={89 23}, pages={237005} }