Magnetic properties of vortex states in spherical superconductors

Abstract

Using a fully three-dimensional numerical treatment of the Ginzburg--Landau (GL) theory, we study superconducting and magnetic properties of submicron superconducting spheres. Systematic analysis is performed for different radii of the sphere and different constituent materials, i.e., with different GL parameter $\ensuremath{\kappa}$. The distribution of the magnetic field in and around the sample is calculated, and its repercussions on magnetometry measurements are discussed. Furthermore, we demonstrate a unique feature in the magnetization curves that can distinguish multi- from giant-vortex states.