General corner states in 2D SSH model with intracelluar next-nearest-neighbour hopping

Xun-Wei Xu, Yu-Zeng Li, Zheng-Fang Liu +1

We investigate corner states in a photonic two-dimensional (2D) Su-Schrieffer-Heeger (SSH) model on a square lattice with zero gauge flux. By considering intracelluar next-nearest-…