Transition between Tamm-like and Shockley-like surface states in optically induced photonic superlattices

Abstract

We study the formation of Shockley-like surface states and their transition into Tamm-like surface states in an optically induced semi-infinite photonic superlattice. While perfect Shockley-like states appear only when the induced superlattice with alternating strong and weak bonds is terminated properly with an unperturbed surface, deformed Shockley-like surface states often appear in the so-called inverted band gap when the surface perturbation is nonzero. Furthermore, transitions between linear Tamm-like, Shockley-like, and nonlinear Tamm-like surface states are also observed by fine tuning the surface perturbation. Using coupled-mode theory, we confirm the existence of these linear and nonlinear surface states in a finite array of $N$ identical single-mode waveguides coupled with alternating strong and weak bonds.