Synthesis of Curved Surface Plasmon Fields through Thin Metal Films in a Tandem Array

We describe the generation of plasmonic modes that propagate in a curved trajectory inducing magnetic properties. This is performed by masking a metal surface with two screens containing a randomly distributed set of holes that follow a Gaussian statistic. The diameter of the holes is less than the wavelength of the illuminating plane wave. By implementing scaling and rotations on each screen, we control the correlation trajectory and generate long-range curved plasmonic modes. Using the evanescent character of the electric field, the study is implemented for the transmission of a plasmonic mode propagating in a tandem array of thin metal films offering the possibility to generate localization effects

Numerical calculation of near field scalar diffraction using angular spectrum of plane waves theory and FFT

t is a known fact that near field diffraction or Fresnel diffraction calculations are difficult to perform exactly. It is in general necessary to make some approximations in order to obtain a more suitable form. In this work, a numerical implementation based on angular spectrum theory for near field diffraction is presented. The method uses Fast Fourier Transforms (FFT) and it turns out to be accurate and fast. In order to show the capabilities of the method, diffraction near field for a circular aperture and a spiral slit are studied. Numerical and experimental results are shown. This method could be useful to implement pc based physical optics learning

Ramírez-San-Juan, Exact solutions for coherent modes of propagation-invariant optical field

Abstract: The exact solution of partial differential equation for coherent-mode propagation of optical field are obtained under the condition of the statistical invariance in propagation direction and for different types of assigning the mode orthonormality. The examples of propagation-invariant fields of different classes are considered