Multilayered structures with high subwavelength resolution based on the metal-dielectric composites

Pure noble metals are usually considered to be negative-permittivity materials for multilayered structures. Such structures can produce flat equal-frequency contours and achieve subwavelength resolution by enabling all propagating and partial evanescent components of the source radiation to be transformed into propagating harmonics. We show that using a composite metal-dielectric layer with an appropriate metal filling factor instead of a negative-permittivity layer can facilitate operation at practically any desired wavelength and achieve good resolution (0.057λ) and that appropriate surface termination can improve the quality of imaging effectively.