Ricerc@Sapienza

Iron and its role as soul of life on Earth is addressed in this review as iron is one of the most abundant elements of our universe, forms the core of our planet and that of telluric (i.e., Earth-like) planets, is a major element of the Earth's crust and is hosted in an endless number of mineral phases, both crystalline and amorphous. To study iron at an atomic level inside the bulk of mineral phases or at its surface, where it is more reactive, both spectroscopy and diffraction experimental methods can be used, taking advantage of nearly the whole spectrum of electromagnetic waves.

Bessel-Gauss beams have mainly been proposed in optics as a solution for reducing the on-axis intensity oscillations typical of Bessel beams. Previous investigations on Bessel-Gauss beams are based on a scalar theory in the paraxial approximation, and thus cannot be extended to the microwave range where a fully vectorial approach is needed. Here, the generation of Bessel-Gauss beams through leaky waves is investigated. First, the nondiffractive and focusing properties of Bessel-Gauss beams generated through leaky waves are extensively examined in the frame of a vectorial approach.