Experimental observation of a weakly angle-dispersive photonic bandgap in a hybrid one-dimensional photonic crystal containing ellipse-dispersion metamaterials.

In conventional 1-D photonic crystals (PhCs) constructed entirely by isotropic dielectric thin films, photonic bandgaps (PBGs) exhibit strong angular dispersion. In this Letter, we report an experimental observation of a weakly angle-dispersive PBG in a hybrid 1-D PhC containing ellipse-dispersion metamaterials. As the incident angle increases from 10° to 80°, the central wavelength of the PBG slightly decreases from 1219.05 to 1102.95 nm with a relative shift of only 9.5%. The weakly angle-dispersive PBG shows potential for realizing wide-angle narrow-band filters based on defect modes and wide-angle narrow-band absorbers based on Tamm plasmon polaritons.