AVS 51st International Symposium
    Magnetic Interfaces and Nanostructures Thursday Sessions
       Session MI-ThM

Paper MI-ThM6
Growth and Characterization of PLD Grown Co Doped TiO@sub 2@

Thursday, November 18, 2004, 10:00 am, Room 304A

Session: Magnetic Oxides and Half-Metallics
Presenter: S.T. Prisbrey, UC Davis, Lawrence Livermore National Laboratory
Authors: S.T. Prisbrey, UC Davis, Lawrence Livermore National Laboratory
S.P. Vernon, Lawrence Livermore National Laboratory
Correspondent: Click to Email
14-20 nm thick 3.7%Co doped TiO@sub 2@ and 5.4% Co doped TiO@sub 2@ have been grown by PLD on LaAlO@sub 3@ (100) substrates. @theta@-2@theta@ x-ray diffraction scans suggest that the films are crystalline and oriented with the z-axis perpendicular to the film surface. AFM/MFM scans show the film to be smooth but with a high defect density (~10@super 6@/cm@super 2@). Defects on the surface of the film do have a magnetic response. X-ray absorption spectroscopy with CoTiO@sub 3@, CoO, and Co@sub 3@O@sub 4@ shows the cobalt to be in the Co@super +2@ formal oxidation state in the majority of the films grown but with no discernable correlation between known deposition parameters and the formal oxidation state of the Co. SQUID magnetic measurements and VSM measurements show that the films are magnetic at room temperature with T@sub c@ > 340°C. Surface ion mass spectrometry was employed to determine that the actual cobalt concentrations in the films are the same as those of the target. Samples were cooled in a field and B-H loops were measured to determine if the magnetic interaction is similar to that of a spin glass.