Spectral response of Cantor multilayers made of materials with negative   refractive index
  Whereas Cantor multilayers made of an isotropic dielectric-magnetic material with positive refractive index will show power-law characteristics, low-order Cantor multilayers made of materials with negative refractive index will not exhibit the power-law nature. A reason for this anomalous behavior is presented. 
Jaline Gerardin, Akhlesh Lakhtakia