Enhanced superconductivity in aluminum-based hyperbolic metamaterials

One of the most important goals of condensed matter physics is materials by design, i.e. the ability to reliably predict and design materials with a set of desired properties. A striking example is the deterministic enhancement of the superconducting properties of materials. Recent experiments have demonstrated that the metamaterial approach is capable of achieving this goal, such as tripling the critical temperature Tc in Al-Al2O3 epsilon near zero (ENZ) core-shell metamaterial superconductors. However, transport properties of such metamaterials remained much worse compared to conventional superconductors. Here, we demonstrate that an Al/Al2O3 hyperbolic metamaterial geometry is capable of a similar Tc enhancement, while having superior transport and magnetic properties compared to the core-shell metamaterial superconductors. This result opens up numerous new possibilities for metamaterial enhancement of Tc in other practically important simple superconductors, such as niobium and MgB2. It also indicates that the recently discovered hyperbolic properties of high Tc superconductors may play considerable role in superconductivity enhancement in cuprates.