Magnetic Pinning of Vortices in a Superconducting Film: The   (anti)vortex-magnetic dipole interaction energy in the London approximation
  The interaction between a superconducting vortex or antivortex in a superconducting film and a magnetic dipole with in- or out-of-plane magnetization is investigated within the London approximation. The dependence of the interaction energy on the dipole-vortex distance and the film thickness is studied and analytical results are obtained in limiting cases. We show how the short range interaction with the magnetic dipole makes the co-existence of vortices and antivortices possible. Different configurations with vortices and antivortices are investigated. 
M. V. Milosevic, S. V. Yampolskii, and F. M. Peeters