Magnetic and superconducting properties of CMR/HTS multilayers for spin injection devices

We report substantial improvement in the critical current in HTS thin film due to the influence of colossal magnetoresistance (CMR) films in YBa2Cu3Ox-based multilayers for spin injection devices. The effect of the CMR strongly depends on the thickness of the HTS, CMR and the intermediate insulator layers. We argue that the improvement in critical current may be due to the self injection of the spin polarized electrons from the CMR to I-ITS, opposite to that normally observed in current driven spin injection devices.