title: Enhanced optical transmission and Fano resonance through a nanostructured metal thin film.
abstract: Artificial and engineered nanostructures expand the degrees of freedom with which one can manipulate the intricate interplay of light and matter. Certain nanostructural arrangements in the excited state enable the efficient electromagnetic coupling of propagating light with localized fields. Here, we demonstrate that light transmitted through a nanostructured metal thin film without any apertures can be significantly enhanced. Distinct asymmetric Fano resonances are observed in the zero-order transmission spectra using an incoherent light source. The transmission efficiency surpasses that of a metal thin film with the same area and thickness at the resonance maxima. The transmission minima and the sharp resonance maxima bear a strong resemblance to the extraordinary optical transmission observed in sub-wavelength nanohole array structures The resonance wavelength closely matches the nanostructural periodicity. The sensitivity of the resonances to the surrounding medium and the transmission efficiency demonstrate the potential for use in energy harvesting, imaging, optical processing and sensing applications.
authors.affiliation: Department of Engineering and Center for Materials Research, Norfolk State University, Norfolk, VA 23504, USA.
authors.forename: Bo
authors.initials: B
authors.lastname: Xiao
authors.affiliation: Department of Engineering and Center for Materials Research, Norfolk State University, Norfolk, VA 23504, USA.
authors.forename: Sangram K
authors.initials: SK
authors.lastname: Pradhan
authors.affiliation: Department of Engineering and Center for Materials Research, Norfolk State University, Norfolk, VA 23504, USA.
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Santiago
authors.affiliation: Department of Engineering and Center for Materials Research, Norfolk State University, Norfolk, VA 23504, USA.
authors.forename: Gugu N
authors.initials: GN
authors.lastname: Rutherford
authors.affiliation: Department of Engineering and Center for Materials Research, Norfolk State University, Norfolk, VA 23504, USA.
authors.forename: Aswini K
authors.initials: AK
authors.lastname: Pradhan