Active Spoof Magnetic Localized Surface Plasmons

In this work, we propose an active spoof magnetic localized surface plasmonic metamaterial that can realize the dynamic control of electric and magnetic resonances in an ultrathin corrugated metallic spiral disk. Active component of varactor has been loaded into such metallic spiral disk structure. By changing the supplied voltages of the active devices, the resonant frequencies of the electric- and magnetic-dipole can be dynamically tuned, thereby flexibly controlling the multipole interference of electric and magnetic resonances. Experimental results are in good agreement with the simulated ones.