Impact of [formula omitted]-symmetric imaginary potentials on edge states of one-dimensional rhombus lattice

Abstract

We theoretically investigate the band structure of the one-dimensional rhombus lattice by considering the existence of PT-symmetric imaginary potentials. Results show that the effects of such potentials are tightly determined by their presence manners. When they are applied to the end sites of the lattice, topological edge states can be efficiently modulated. Meanwhile, more edge states caused by PT-symmetry imaginary potential appear in the system, and the system undergoes the spontaneous PT-symmetry breaking transition. When local magnetic flux is incorporated, edge states can be further adjusted. However once PT-symmetric imaginary potentials are added to each unit cell of the lattice, they are less effective in manipulating the edge states despite the modification in the band structure. Based on these results, we better comprehend the adjustability of the edge states of the rhombus lattice by applying the PT-symmetric imaginary potentials.