Abstract: A system includes a magneto-dielectric metasurface including one or more screens of the plurality of screens including at least one track, with a specific shape, juxtaposed to one face of a layer, configured to suppress at least unwanted incident right-hand circularly polarized plane waves. A system includes a metasurface polarizer including one or more screens of the plurality of screens including a plurality of layers and a plurality of tracks having a specific shape for each layer and interposed between the layers, configured to convert the incident linear/circularly polarized wave into left-hand circular polarization. A system may include a phase shift metasurface including one or more screens of the plurality of screens including at least one layer with at least one track on each side of the layer, configured to cancel the transmitted and reflected waves at the antenna point and suppress the incident wave consequently.

Abstract: An electrically pumped VCSEL and a method of its fabrication are presented. The VCSEL comprises an active cavity material sandwiched between top and bottom DBR stacks, the top DBR having at least one n-semiconductor layer. The device defines an aperture region between the structured surface of the active cavity material and the n-semiconductor layer of the top DBR stack. The structured surface is formed by a top surface of a mesa that includes at least the upper n++ layer of a p++/n++ tunnel junction and the surface of a p-type layer outside the mesa. The structured surface is fused to the surface of the n-semiconductor layer of the DBR stack due to the deformation of these surfaces, thereby creating an air gap in the vicinity of the mesa between the fused surfaces.