Striking properties of light transmitted by a double period nanoslit structure under evanescent incidence

MARCELO LESTER; DIANA SKIGIN

JOURNAL OF OPTICS. A, PURE AND APPLIED OPTICS (PRINT)

IOP PUBLISHING LTD

Lugar: Londres; Año: 2015

1464-4258

The excitation of phase resonances in dual-period wire structures under evanescent incidenceis investigated and numerically reported for the first time. The diffraction problem of a com-pound structure comprising subwavelength perfectly conducting wires and slits near a dielectricinterface is solved by the modal method, which has been extended to consider evanescent in-cidence via illumination under the total internal reflection (TIR) condition. We demonstrateevanescent-to-propagating conversion in the transmitted intensity via resonances of differenttypes, such as Fabry-Perot and Rayleigh anomalies. The results exhibit points in common withthose obtained for simple structures (single wire/slit per period), but, on the other hand, thereare striking differences, mainly arising from the excitation of phase resonances in the structure.These features allow an angular and spectral control of the transmitted response, which opensup new degrees of freedom for the design of input/output couplers and other devices.