Enhanced and controllable reflected group delay based on Tamm surface plasmons with Dirac semimetals

Abstract In this paper, the reflected group delay from a multilayer structure where bulk Dirac semimetals (BDS) is coated on one-dimensional photonic crystal (1D PC) separated by spacer layer investigated theoretically. It shown that of beam in can be significant enhanced negatively and switched negative to positive. The originates steep phase change caused excitation optical Tamm state (OTS) at interface between BDS layer. Moreover, positive actively tuned through Fermi energy relaxation time BDS. We believe tunable scheme has important research significance for fabrication devices.