Photonic bandgaps for grating-coupled waveguide modes with a silver tunnel barrier
Hooper, Ian R.
Sambles, J. Roy
University of Exeter
New Journal of Physics
Institute of Physics and Deutsche Physikalische Gesellschaft
The optical properties of a periodically modulated photoresist waveguide structure has been explored using the Kretschmann–Raether configuration with a thin silver tunnel barrier. A detailed experimental study of how wavelength-scale periodic texture modifies the dispersion of the guided modes in the visible range for a wide range of azimuthal angles is presented. Fitting the observed in-plane momenta of the modes to predictions from a multilayer, multishape differential grating theory model allows the identities of each of the modes to be confirmed. In addition, the intensities obtained experimentally are compared favourably with those predicted from a theoretical model. Such a waveguide structure can produce not only the photonic bandgaps at the Brillouin zone boundary, but also bandgaps within the Brillouin zone caused by the Bragg scattered guided modes anti-crossing with the unscattered modes. All of these photonic bandgaps have potential applications controlling spontaneous emission in devices.
Copyright © 2007 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft. This is the published version of an article published in New Journal of Physics Vol. 9, article 251. DOI: 10.1088/1367-2630/9/8/251
9, article 251