Impact of Impurities on the Topological Boundaries and Edge State Localization in a Staggered Chain of Atoms: SSH Model and Its Topoelectrical Circuit Realization

We study the Su-Schrieffer-Hegger model, perhaps the simplest realization ofa topological insulator, in the presence of an embedded impurity superlattice.We consider the impact of the said impurity by changing the hopping amplitudesbetween them and their nearest neighbors in the topological boundaries and theedge state localization in the chain of atoms. Within a tight-binding approachand through a topolectrical circuit simulation, we consider three differentimpurity-hopping amplitudes. We found a relaxation of the condition betweenhopping parameters for the topologically trivial and non-trivial phase boundaryand a more profound edge state localization given by the impurity positionwithin the supercell.