Theoretical modeling of critical temperature increase in metamaterial superconductors

Recent experiments have demonstrated that the metamaterial approach is capable of drastic increase of the critical temperature T c of epsilon near zero (ENZ) metamaterial superconductors. For example, tripling of the critical temperature has been observed in Al-Al 2 O 3 ENZ core-shell metamaterials. Here, we perform theoretical modelling of T c increase in metamaterial superconductors based on the Maxwell-Garnett approximation of their dielectric response function. Good agreement is demonstrated between theoretical modelling and experimental results in both aluminium and tin-based metamaterials. Taking advantage of the demonstrated success of this model, the critical temperature of hypothetic niobium, MgB 2 and H 2 S-based metamaterial superconductors is evaluated. The MgB 2-based metamaterial superconductors are projected to reach the liquid nitrogen temperature range. In the case of an H 2 S-based metamaterial T c appears to reach ~250 K.