Resonant diffraction of symmetric and antisymmetric Bloch surface waves on a corrugated periodic multilayer slab.
A mechanism for resonantly diffracting surface waves is presented. Symmetric and antisymmetric Bloch surface modes, prism coupled via evanescent coupling on a one-dimensional photonic crystal slab, are backdiffracted by means of a very shallow sinusoidal grating located on the top of the slab. At a given wavelength, resonant diffraction is produced when the grating vector equals the spatial beat frequency between the two modes. The presented mechanism is particularly attractive in optical sensing schemes in which both a high surface sensitivity and high diffraction efficiencies are required.
Descrovi
Emiliano
E
Materials and Microsystems Laboratory xLab, Politecnico di Torino, Torino, Italy. emiliano.descrovi@polito.it
D008029:Lighting; D055096:Optical Devices; D013499:Surface Properties