Abstrakt: |
We assume a two-dimensional array of ferromagnetic particles on the surface of a thin type-II superconductor in a transverse magnetic field. With a particle at the center of each fluxoid, the pinning forceP and critical current increase ?Jc due to the particles are calculated. General expressions without arbitrary parameters are given forP and ?Jc as functions of magnetic field strength and the characteristics of the superconductor and the particles. For broad ranges of conditions values ofP and ?Jc greater than 10-7 dyn and 105 A/cm2 result and for certain physically realistic sets of conditions,P>10-6 dyn and ?Jc>106 A/cm2 are predicted. The above effects should be readily observable. An experiment for setting up the assumed conditions is proposed and discussed in some detail. |