title: Two-dimensional grating for narrow-band filtering with large angular tolerances.
abstract: A two-dimensional periodic sub-wavelength array of vertical dielectric cylinders on a glass substrate is studied numerically using three different electromagnetic approaches. It is shown that such structure can present a narrow-band spectral resonance characterized by large angular tolerances and 100% maximum in reflection. In particular, in a two-nanometer spectral bandwidth the reflectivity stays above 90% within angles of incidence exceeding 10 degrees for unpolarized light. Bloch modal analysis shows that these properties are due to the excitation of a hybrid mode that is created in the structure by a guided-like mode and a localized cavity mode. The first one is due to the collective effect of the array, while the second one comes from the mode(s) of a single step-index fiber.
authors.forename: Evgeny
authors.initials: E
authors.lastname: Popov
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Fehrembach
authors.forename: Yoann
authors.initials: Y
authors.lastname: Brûlé
authors.forename: Guillaume
authors.initials: G
authors.lastname: Demésy
authors.forename: Philippe
authors.initials: P
authors.lastname: Boyer