title: Transmission enhancement through square coaxial aperture arrays in metallic film: when leaky modes filter infrared light for multispectral imaging.
abstract: The diffractive behavior of arrays of square coaxial apertures in a gold layer is studied. These structures exhibit a resonant transmission enhancement that is used to design tunable bandpass filters for multispectral imaging in the 7-13 μm wavelength range. A modal analysis is used for this design and the study of their spectral features. Thus we show that the resonance peak is due to the excitation of leaky modes of the open photonic structure. Fourier transform infrared (FTIR) spectrophotometry transmission measurements of samples deposited on Si substrate show good agreement with numerical results and demonstrate angular tolerance of up to 30 degrees of the fabricated filters.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Vial
authors.forename: Mireille
authors.initials: M
authors.lastname: Commandré
authors.forename: Guillaume
authors.initials: G
authors.lastname: Demésy
authors.forename: André
authors.initials: A
authors.lastname: Nicolet
authors.forename: Frédéric
authors.initials: F
authors.lastname: Zolla
authors.forename: Frédéric
authors.initials: F
authors.lastname: Bedu
authors.forename: Hervé
authors.initials: H
authors.lastname: Dallaporta
authors.forename: Stéphane
authors.initials: S
authors.lastname: Tisserand
authors.forename: Laurent
authors.initials: L
authors.lastname: Roux