Emitting and negatively-refractive focusing apparatus, methods, and systems

摘要

Apparatus, methods, and systems provide emitting and negatively-refractive focusing of electromagnetic energy. In some approaches the negatively-refractive focusing includes negatively-refractive focusing from an interior field region with an axial magnification substantially less than one. In some approaches the negatively-refractive focusing includes negatively-refractive focusing with a transformation medium, where the transformation medium may include an artificially-structured material such as a metamaterial.

主权项

1. A method, comprising:
determining electromagnetic parameters that define a negative refractive index in a spatial region, the electromagnetic parameters providing an axial magnification less than one for an interior field region within the spatial region; configuring an artificially-structured material having an effective electromagnetic response that corresponds to the electromagnetic parameters in the spatial region; and selecting one or more positions of one or more electromagnetic emitters within the spatial region, wherein the one or more positions are inside the interior field region, wherein the electromagnetic parameters provide an exterior focusing region for electromagnetic waves that radiate from the interior field region; wherein the electromagnetic parameters define a transformation medium; wherein the transformation medium corresponds to a multiple-valued coordinate transformation; and wherein a first branch of the multiple-valued coordinate transformation maps an untransformed region to the exterior focusing region, and a second branch of the multiple-valued coordinate transformation maps the untransformed region to the interior field region.