Structure and functionalities of manganite/cuprate thin film.

Bilayer thin film samples consisting of colossal magnetoresistance manganite La 0.7 Ca 0.3 MnO 3 (LCMO) and superconducting cuprate YBa 2 Cu 3 O 7−δ (YBCO) were stabilized by means of pulsed laser deposition techniques on single crystal SrTiO 3 (001) substrate. The X-ray diffraction measurements confirm the epitaxial relationship of grown bilayer samples. The functional properties of the LCMO/YBCO bilayer were explored through magnetic and electrical transport measurements. The magnetization curve of LCMO/YBCO bilayer sample retains the characteristic ferromagnetic-paramagnetic transition of LCMO and superconducting transition of YBCO. The electrical resistivity was found to show different trend around the superconducting transition depending upon the four probe electrical contacts configuration on bilayer samples and the obtained results lead to direct visualization of proximity effect. A change in sign of magnetoresistance near the superconducting and metal to insulator transition temperature is observed which is attributed to the intrinsic property of YBCO and LCMO layers. [ABSTRACT FROM AUTHOR]