Topological Transition Metasurfaces for Manipulating Terahertz Surface Wave Propagation

Metasurfaces refer to planarized ultrathin metamaterials which promise an effective approach to control not only waves in the free space but also surface plasmon polaritons (SPPs) which is an attractive form of electromagnetic waves propagating along the interface between typical metals and dielectrics. Topological transition metasurfaces have emerged as a fascinating platform to control SPPs. In this work, we propose topological transition metasurfaces for achieving anomalous terahertz surface wave propagation. Combining different complementary H-shape resonators, we observe anomalous wave propagation at the interface where eigenmode of the resonator experiences topological transition. The proposed metasurfaces open unprecedented venues for anomalous surface wave propagation and guidance which show great capabilities for designing photonic devices.