Improving the critical temperature of MgB2 superconducting metamaterials induced by electroluminescence

The MgB2 superconductor was doped with electroluminescent Y2O3:Eu, to synthesise a superconducting metamaterial. The temperature dependence of the resistivity of the superconductor indicates that the critical temperature (TC) of samples decrease when increasing the amount of doped Y2O3 nanorods, due to impurity (Y2O3, MgO and YB4). However, the TC of the samples increase with increasing amount of doped Y2O3:Eu3+ nanorods, which are opposite to doped Y2O3 nanorods. Moreover, the transition temperature of the sample doped with 8 wt. % Y2O3:Eu3+ nanorods is higher than those of doped and pure MgB2. The TC of the sample doped with 8 wt. % Y2O3:Eu3+ nanorods is 1.15 K higher than that of the sample doped with 8 wt. % Y2O3. The TC of sample doped with 8 wt. % Y2O3:Eu3+ is 0.4 K higher than that of pure MgB2. Results indicate that doping electroluminescent materials into MgB2 increases the transition temperature; this novel strategy may also be applicable to other superconductors.