Zero-admittance states in honeycomb topological circuits

Abstract

Topological circuits play an important role in exploring high-order topological insulators. In this work, we demonstrate that defects in the bulk without changing the parameters can increase zero-admittance states. Furthermore, the coupling parameters affect the distribution of the zero-admittance states are demonstrated. The impedance is measured to verify the existence of these states. The experimental results agree well with the theoretical results, both showing the strong resonance peak, as well as the impedance distribution of different parameters is mainly concentrated at the 2π/3 corner, 2π/6 corner, or edge. Our work paves the way for the research and experimentation of honeycomb topological circuits.