Fabry–Pérot resonance coupling associated exceptional points in a composite grating structure

Jiang Zhi-Sen^{1, 2}, Hu De-Jiao³, Pang Lin^{1, 2, †}, Gao Fu-Hua^{1, 2}, Wang Ping^{1, 2}

(color online) (a) Forward reflection spectrum as a function of interval G and wavelength λ, with H = 1900 nm and h = 10.6 nm, and other parameters are the same as those in Fig. 1(a). The white dashed line represents aperture mode and white solid line refers to gap mode. The white arrow points to the zero reflection points 1 and 2 both at G = 751 nm. ((b), (c)) Forward phases of reflection coefficients in the vicinity of points 1 and 2.