High-frequency vortex matching effects in Pb thin films with a periodic array of antidots

We study the vortex dynamics and flux-pinning properties of a superconducting thin film of lead with a periodic array of microholes (antidots) by performing high-frequency measurements. We report the first experimental observation of commensurability effects of the vortex lattice at matching magnetic fields in the magnetic field dependence of the modulus of the microwave complex reflection coefficient S11 for different temperatures, frequencies and radiation powers.