Uniaxial superconducting particle in intermediate magnetic fields

The problem of an anisotropic uniaxial superconducting particle of a general ellipsoidal form in the magnetic field $H_0$ such that $H_{c1\mathrm{}}\ll H_0\ll H_{c2\mathrm{}}$, is considered. It is shown—in agreement with experimental data—that particles of high-$T_c$ materials at $T<\mathrm{}{T}_c$ must orient with their $c$ axis normal to the applied field. The torque acting on a particle is evaluated and shown to be independent of the ellipsoid shape. The torque is associated with the magnetization component perpendicular to the field direction.