Resonant backward scattering of light by a subwavelength metallic slit with two open sides

Abstract

The backward scattering of TM-polarized light by a two-side-open subwavelength slit in a metal film is analyzed. We show that the reflection coefficient versus wavelength possesses a Fabry-Perotlike dependence that is similar to the anomalous behavior of transmission reported in the study [Y. Takakura, Phys. Rev. Lett. 86, 5601 (2001)]. The open slit totally reflects the light at the near-to-resonance wavelengths. In addition, we show that the interference of incident and resonantly backward-scattered light produces in the near-field diffraction zone a spatially localized wave whose intensity is 10-10 3 times greater than the incident wave, but one order of magnitude smaller than the intra-cavity intensity. The amplitude and phase of the resonant wave at the slit entrance and exit are different from that of a Fabry-Perot cavity.

Visible light dynamical diffraction in a 1-D photonic crystal-based interferometer with an extremely thin spacer layer

“…Here it is interesting to mention that a cavity in the shape of a ten nanometer-sized slit in a conducting metal film also demonstrates optical properties which are inherent to a Fabry-Pérot resonator/interferometer [30][31][32]. Fig.…”

Enhanced Transmission and Reflection of Few-Cycle Pulses by a Single Slit

“…Inside the slit, the maxima are slightly shifted from that of the cw [8]. The effect is caused by the internal reflection of the pulse at the slit entrance and exit.…”

“…Experiments as well as computations were performed to investigate this problem for various parameters: pulse length, object shapes and sizes, etc. [3][4][5][6][7][8][9][10][11][12][13][14][15]. It was shown that the scattering process alters the pulse shape and spectrum, resulting in various effects such as pulse broadening, compression, time delay or advancement, and spectral shifts.…”

“…It was shown that the scattering process alters the pulse shape and spectrum, resulting in various effects such as pulse broadening, compression, time delay or advancement, and spectral shifts. The recent studies showed that the transmission of few-cycle (terahertz [4] and femtosecond [8]) pulses through a single slit can be enhanced at appropriate resonant conditions. Although a general point of view has been suggested on the physics underlying the enhanced transmission and reflection of ultrashort pulses by various nanostructured materials, as due to excitation of the long-living quasistationary eigenstates of the effective Hamiltonian for the Maxwell theory [12], a detailed investigation of the problem for the most fundamental system of wave physics (a single slit) is required.…”

“…We presented the analysis for different pulse durations at fixed values of 2a 0 =32, b 0 =2:315, and 0 , where these values correspond to the resonant conditions for enhancement of cw according to Ref. [8]. Naturally, the variation of the parameters a, b, and 0 modify the electromagnetic field, but there are always three propagation regimes whose main characteristics remain the same.…”