Comment on 'Perfect drain for the Maxwell fish eye lens'
  The non-magnetic loss material has been proposed (2011 New J. Phys. 13 023038) to mimic a passive perfect drain in the Maxwell's fish eye lens (MFL). In this comment, we argue that this passive medium can only be treated as a perfect absorber which can totally absorb all incident radiation without scattering by it, but it cannot mimic a perfect focusing point. As a result, this passive medium cannot help to achieve a perfect focusing in MFL. 
Fei Sun
physics.optics