Commensurability effects in overlap Josephson junctions coupled with a   magnetic dots array
  Experimental observation of the strong influence of an array of ferromagnetic nanodots on the critical current of a short overlap Josephson junction is reported. Pronounced commensurability effects are detected due to the presence of the additional peaks in the magnetic field induced diffraction pattern. The changes in the Fraunhofer pattern of the Josephson junctions are account for by the formation of Abrikosov vortices trapped in the electrodes which induce a phase inhomogeneity in the junction area. 
S.N. Vdovichev, S.A. Gusev, Yu.N. Nozdrin, A.V. Samokhvalov, A.A.   Fraerman, E. Il'ichev, R. Stolz, L. Fritzsch