The transmission spectrum of 1D-FGPC (T₃) structure as a function of the light frequency in the cases of (a) σ_g ≠ 0 (solid red curve) and (b) σ_g = 0 (dotted blue curve) for the normal incidence of the waves. Temperature and chemical potential are chosen as T = 300 K and μ_C = 0.2 eV.