Transmission through subwavelength slit structures with double period: simple model for the prediction of resonances

DIANA CARINA SKIGIN

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

IOP PUBLISHING LTD

Año: 2009 vol. 11 p. 105102 - 105102

1464-4258

Transmission wire gratings comprising several subwavelength slits within each period(compound gratings) have been shown to exhibit abrupt dips in the transmission response.These minima correspond to phase resonances, that are excited in the structure when aparticular distribution of the magnetic field phases inside the slits is generated. By using anapproximate model based on the modal method, we can easily obtain the resonant frequencieswhich correspond to transmittance maxima (Fabry–Perot resonances) and minima (phaseresonances). This simplified model constitutes a practical tool to accurately predict the relevantcharacteristics of the transmitted response of compound structures for normal and obliqueincidence, without a full solution of the scattering problem.