Gaussian Beams in Near-Zero Transition Metamaterials
  We theoretically and numerically investigate the phenomenon of resonant field enhancement of Gaussian beams in two types of transition metamaterials: with a positive-zero-negative index profile and with a positive-zero-positive index profile and demonstrate strongly localized resonant field enhancement in both cases. This study is likely to have applications in the fields of nano-optics, sub-wavelength imaging, and nano-fabrication and lays a foundation for the studies of more complex vector and vortex beam propagation in graded-index metamaterials. 
Fatema Alali and Natalia M. Litchinitser
physics.optics