US Patent 11536903 Hybrid edge couplers with stacked inverse tapers

Structures for an edge coupler and methods of fabricating a structure for an edge coupler. A first waveguide core has a first section that has a tapered shape and a second section that is adjoined to the first section. Multiple segments are positioned with a spaced arrangement adjacent to an end surface of the second section of the first waveguide core. A slab layer is adjoined to the first section of the first waveguide core. A second waveguide core has a section that overlaps with the first section of the first waveguide core to define a layer stack. The section of the second waveguide core has a tapered shape, and the first and second waveguide cores are comprised of different materials. The first section of the first waveguide core has a first thickness, and the slab layer has a second thickness that is less than the first thickness.