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The development of surface plasmon polariton (SPP) optical elements is mandatory in order to achieve
surface plasmon based photonics. A current approach to reach this goal is to take advantage of the interaction
of SPP with defects and design elements obtained by the micro- or nano-structuration of the metal film. In this
work, we have performed a detailed study of the performance and behavior of SPP-Bragg mirrors, designed for
45° incidence, based on this approach. Mirrors consisting of gratings of both metal ridges on the metal surface
and grooves engraved in the metal, fabricated by means of electron beam lithography and focused ion beam,
have been considered. The performance of the mirrors has been characterized via near-field optical microscopy.
An original procedure to obtain quantitative values of the mirrors' reflectivity and transmission coefficient from
the near-field images is exposed. The mirrors composed of metal ridges are shown to act very efficiently, and
a rather low number of elements (15 for the specific geometry studied) is able to deflect almost 100% of the
incoming power. Conversely, the arrays of grooves produce a much lower reflectivity, which we attribute
mostly to radiative scattering in the forward direction induced by the grooves. Besides, the considered systems
have also been simulated by using the differential method. The results obtained from the numerical calculations
present an excellent agreement with the experimental data, proving the reliability of this method to predict the
behavior of this kind of systems while interacting with SPP. Based on the numerical modeling of the SPP-Bragg
mirrors, the evolution of the mirrors' behavior with the ridges height is analyzed..
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