  Fractal metamaterial superconductor geometry has been suggested and analyzed
based on the recently developed theoretical description of critical temperature
increase in epsilon near zero (ENZ) metamaterial superconductors. Considerable
enhancement of critical temperature has been predicted in such materials due to
appearance of large number of additional poles in the inverse dielectric
response function of the fractal. Our results agree with the recent observation
(Fratini et al. Nature 466, 841 (2010)) that fractal defect structure promotes
superconductivity.
