Rectangular empty waveguide transition for realizing an electromagnetic jet based measuring device

Spheres, cylinders, cones, cuboids have been used in the literature to generate photonic jets at the back of these structures when illuminated by plane waves. We are working on the generalization (which we call electromagnetic jet) of this concept in guided structures in the microwave domain. The electromagnetic jet can be obtained from a rectangular waveguide loaded with dielectric. In order to use the electromagnetic jet as a localized measurement tool, it is therefore necessary to address the adaptation between an empty rectangular waveguide and a loaded guide. This is the object of the work presented here, where two solutions are compared.