Antidot diameter dependence of matching effect in Bi2Sr2CaCu2O8+y with antidot array

To explore vortex states and their dynamics in superconductors with large thermal fluctuation and artificial pinning potentials, we have studied the influence of periodic arrays of antidots in high-T_c superconductor Bi₂Sr₂CaCu₂O_8+y (Bi2212). The diameter dependence of the matching effect in Bi2212 without a change of the thickness and oxygen doping level was investigated using one Bi2212 single-crystal film of homogeneous thickness in which several different-diameter antidot arrays were introduced. The matching effect observed by vortex-flow resistance measurements changed systematically depending on the diameter. The antidot-diameter dependence of the irreversibility lines was examined.