Mode Evolution and Transmission Suppression in a Perforated Ultrathin Metallic Film with a Triangular Array of Holes
نویسندگان
چکیده
We theoretically study the evolution of the resonant modes and the transmission suppression (TS) effect in a perforated ultrathin metallic film (PUMF) with a periodic triangular array of holes. It is found that the properties of different resonances change as the hole radius increases, and the non-monotonic shift of resonant frequency can be interpreted qualitatively from the electric field distribution other than the Fano model. In addition, we analyze the strong mode interaction phenomenon in PUMF. When the diameter of holes approaches to four fifths of the lattice constant, the coupling between dipolar resonance and decapolar resonance can lead to an anticrossing and a large Rabi splitting, which is not available in PUMFs with square lattice; the resulting hybrid modes can be ascribed to the quasi-inphase and quasi-antiphase interferences between dipolar resonance and decapolar resonance. By comparing the TS effect of different resonances under different hole radii, we conclude that although dipolar resonance, short-range surface plasmons, and hybrid modes can all contribute to TS effect; the prominent TS effect in our structure should be mainly caused by the collective dipolar resonance of the structure. These findings might be of interest for the future studies in PUMF-based structures and devices.
منابع مشابه
Strong light concentration at the subwavelength scale by a metallic hole-array structure.
A metallic two-dimensional hole-array (2DHA) sample is successfully fabricated and its transmission property measured at mid-infrared wavelengths (lambda ~ 1.5-20 microm). At the plasmonic resonance, the 2DHA sample exhibits a normal incidence transmittance of 80% at lambda = 7.6 microm. This corresponds to more than twice as much light that is transmitted as it impinges directly on the holes a...
متن کاملMetamaterial-plasmonic absorber structure for high efficiency amorphous silicon solar cells.
We show that a planar structure, consisting of an ultrathin semiconducting layer topped with a solid nanoscopically perforated metallic film and then a dielectric interference film, can highly absorb (superabsorb) electromagnetic radiation in the entire visible range, and thus can become a platform for high-efficiency solar cells. The perforated metallic film and the ultrathin absorber in this ...
متن کاملPolarization effects in metallic films perforated with a bidimensional array of subwavelength rectangular holes
For several years, periodical arrays of subwavelength cylindrical holes in thin metallic layers have taken a crucial importance in the context of the results reported by Ebbesen et al, on particularly attractive optical transmission experiments. It had been underlined that the zeroth order transmission pattern does not depend on the polarization of the incident light at normal incidence. In the...
متن کاملSecond-Order Nonlinearity in Triangular Lattice Perforated Gold Film due to Surface Plasmas Resonance
We have studied the excitation second-order nonlinearity through a triangular lattice perforated gold film instead of square lattice in many papers. Under the excitation of surface plasmas resonance effect, the second order nonlinearity exists in the noncentrosymmetric split-ring resonators arrays. Reflection of fundamental frequency wave through a triangular lattice perforated gold film is obt...
متن کاملThe effect of material nonlinearity on the band gap for TE and TM modes in square and triangular lattices
In this article, by using the method of finite difference time domain (FDTD) and PML boundary conditions, we have studied the photonic band gaps for TE and TM modes in square and triangular lattices consisting of air holes in dielectric medium and compared the results. In addition, the effect of nonlinearity of the photonic crystal background on the photonic band gaps and comparison with the re...
متن کامل