Anisotropic Superconducting Properties of Aligned MgB2 Crystallites

Abstract
Samples of aligned MgB2 crystallites have been prepared, allowing for the first time the direct identification of an upper critical field anisotropy Hc2ab/Hc2c=ξab/ξc1.7, with ξo,ab70, ξo,c40, and a mass anisotropy ratio mab/mc0.3. A ferromagnetic background signal was identified, possibly related to the raw materials purity.