Focusing light with typical subwavelength patterned metallic structures

摘要

Two typical subwavelength nano-lenses, nano-slits and nano-grooves, are investigated based on the diffraction and electromagnetic boundary condition. Detailed and systematic analyses for the focusing properties of the two structures with different geometrical parameters are carried out. Theoretical results agree well with those in the numerical simulations and experiments. Compared to the nano-grooves, nano-slits with appropriate geometrical parameters show higher efficiency and better focusing performance.