Experimental observation of optical bandgaps for surface electromagnetic waves in a periodically corrugated one-dimensional silicon nitride photonic crystal.
Dispersion curves of surface electromagnetic waves (SEWs) in 1D silicon nitride photonic crystals having periodic surface corrugations are considered. We experimentally demonstrate that a bandgap for SEWs can be obtained by fabricating a polymeric grating on the multilayered structure. Close to the boundary of the first Brillouin zone connected to the grating, we observe the splitting of the SEW dispersion curve into two separate branches and identify two regions of very low group velocity. The proper design of the structure allows the two folded branches to lie beyond the light line in a wide spectral range, thus doubling the density of modes available for SEWs and avoiding light scattering.
Descrovi
Emiliano
E
Laboratorio Materiali e Microsistemi chiLab, Dipartimento di Fisica, Politecnico di Torino, Torino, Italy. emiliano.descrovi@polito.it
Giorgis
Fabrizio
F
Dominici
Lorenzo
L
Michelotti
Francesco
F
D003460:Crystallization; D004867:Equipment Design; D008027:Light; D015233:Models, Statistical; D055095:Optics and Photonics; D010777:Photochemistry / Q000379:methods*; D017785:Photons; D011108:Polymers / Q000737:chemistry; D011827:Radiation; D015203:Reproducibility of Results; D017655:Silicon Compounds / Q000737:chemistry*; D013053:Spectrophotometry; D013499:Surface Properties
D011108:Polymers; D017655:Silicon Compounds; C032734:silicon nitride