Tuning Plasmonic Cavity Modes By The Symmetry Breaking Of Metasurface

A plasmonic cavity composed from metasurface is designed and experimentally demonstrated. Due to the symmetry breaking of the metasurface, the degeneracy of the different polarized cavity states is lifted. It shifts the resonating frequencies of two polarized cavity modes, in which one is blue-shifted and another is red-shifted. Combining with a photothermal effect, we demonstrate that the polarized cavity states can be experimentally tuned by varying the reflection phase of the metasurface through the incident laser intensity. This reported metacavity can be applied in cavity quantum optics, lasers and other light-matter interaction processes.