Subwavelength localization of near fields in coupled metallic spheres for single-emitter polarization analysis.

We numerically demonstrate selective near-field localization determined by the polarization state of a single emitter coupled to a plasmonic nanocluster. Seven gold nanospheres are carefully arranged such that up to 10 polarization states of the single emitter, including linear, circular, and elliptical polarizations, can be distinguished via the distinct field localization in four gaps. The ability to transform polarization states into field spatial localizations may find application in single emitter polarization analysis.