Anisotropy in a Heavy Fermion Superconductor: UPd_<b>2</b>Al_<b>3</b>

Abstract

We report on the anisotropy of magnetization, electrical resistivity and upper critical magnetic fields ( H C2 ) of UPd 2 Al 3 . The magnetization curve in the antiferromagnetically ordered state shows large anisotropy, indicating that the sublattice moments lie in the basal hexagonal plane. The value of -( d H C2 / d T ) at T C is estimated to be about 36 (kOe/K) for the magnetic field parallel and perpendicular to the hexagonal c -axis, and the upper critical field seems to be rather isotropic.