Angular Dependence of the Fluctuation Magnetization Vector Above the Superconducting Transition of a Highly Anisotropic High-T c Cuprate

Abstract

In highly anisotropic cuprate superconductors it is generally accepted that the reversible magnetization vector, ��⃗ , is essentially perpendicular to the superconducting CuO 2 layers in a wide range of crystal orientations with respect to the applied magnetic field, � �⃗ . In a recent work [J. Mosqueira et al., Phys. Rev. B 84, 134504 (2011)] it is shown, however, that the dependence of ��⃗ on the � �⃗ orientation in the reversible mixed state of a high-quality Tl-based cuprate presents a notable deviation from this behavior. Here we extend these measurements to the fluctuation region above T c , in order to check whether the above mentioned effect is also present.