2018 IEEE 8th International Conference on Nanomaterials: Applications & Properties (NAP – 2018). 2018, 02TSSPN02-1-02TSSPN02-5
By specific design of the sample, in which SrTiO3 substrate is fully covered by a thin film of the colossal magnetoresistive material La0.67Ca0.33MnO3 (LCMO) and the latter is partially covered by high-temperature superconductor YBa2Cu3O7- (YBCO), and by using multiple current and voltage contacts, direct evidence of spin injection from LCMO to YBCO is obtained. It is found that spin-polarized electrons injected from LCMO strongly influence not only superconducting, but also normal state of YBCO. The effect of deposition conditions of LCMO and YBCO and the quality of the interface on the spin injection efficiency is clarified. A surprising peak in the temperature dependence of resistance seen on ex-situ sample is explained as combination of two effects: strong influence of spinpolarized electrons on superconductor just below its critical temperature and the interface-controlled shift of Curie temperature of LCMO to low temperatures. Considering expected use of LCMO and YBCO in composite quantum computation circuits, a possibility of their combination with another advanced quantum material, graphene, is explored.