MAGNETIC FORCE ACTING ON A MAGNETIC POINT DIPOLE OVER A SUPERCONDUCTING THIN-FILM WITH A CIRCULAR DEFECT

London theory is used to calculate the magnetic levitation force actin g on the magnetic point dipole placed above the type-II superconductin g thin film with a circular defect. The condition of the position of p oint dipole to create the first vortex in the thin film is found for b much less than boolean AND. The difference of the lateral magnetic fo rce Delta F-r acting on the point dipole between with and without a si ngle vortex created in the thin film is also derived and used to estim ate the force to overcome the pinning force of the vertex due to the c ircular defect.