Superconducting properties of tin-based ENZ and hyperbolic metamaterials

Recent experiments have demonstrated that the superconducting critical temperature may be improved in various metamaterial superconductor geometries. Here, we present the results of a study of tin-based metamaterial superconductors in the epsilon-near-zero (ENZ) and hyperbolic metamaterial configurations. It was observed that T-c enhancement is significantly reduced when the metamaterial structural dimensions exceed 240 nm, the superconducting coherence length in pure tin.