Manipulating magnetic and magnetoresistive properties by oxygen vacancy complexes in GCMO thin films.

The effect ofannealing is investigated in GdCaMnO(GCMO) thin films in oxygen and vacuum atmospheres. We show that the reduction of oxygen content in GCMO lattice by vacuum annealing induced more oxygen complex vacancies in both subsurface and interface regions and larger grain domains when compared with the pristine one. Consequently, the double exchange interaction is suppressed and the metallic-ferromagnetic state below Curie temperature turned into spin-glass insulating state.

Tuned AFM-FM coupling by the formation of vacancy complex in GdCaMnOthin film lattice.

The effect ofoxygen and vacuum annealings on the low bandwidth manganite GdCaMnO(GCMO) thin film with= 0.4 was investigated. Based on the magnetic measurements, the AFM-FM coupling is suppressed by the vacuum annealing treatment via destroying the double exchange interaction and increasing the unit cell volume by converting the Mnto the Mn.

Control of the nanosized defect network in superconducting thin films by target grain size.

A nanograined YBCO target, where a great number of grain boundaries, pores etc. exist, is shown to hold an alternative approach to future pulsed laser deposition based high-temperature superconductor thin film and coated conductor technologies. Although the nanograined material is introduced earlier, in this work, we comprehensively demonstrate the modified ablation process, together with unconventional nucleation and growth mechanisms that produces dramatically enhanced flux pinning properties.