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The surface of an anatase titanium dioxide (TiO2) film grown on LaAlO3(001) was observed using noncontact atomic force microscopy (NC-AFM). After cleaning with cycles of argon ion sputtering and annealing in vacuum, (1 × 4)- and (1 × 5)-reconstructed terraces appeared. In addition to the terraces, the sputter-annealed surface included many agglomerations. The presence of Tin+ () shown by x-ray photoelectron spectroscopy indicates that the agglomerations are due to TiOx () species. Limited replenishment of oxygen by the substrate and the low diffusivity of the Tin+ to the substrate are possible causes for the generation of the TiOx.

Recent neurobiophysics experiments based on synchrotron spectromicroscopy indicated that aluminium is selectively accumulated by GABAergic neurons and glial cells rather than by granule cells. Does a similar cell specificity occur in the accumulation of other metals? We provide experimental evidence to the contrary: cobalt is found in granule cells at least with equal probability as in glial cells and GABAergic neurons. This result also confirms that neurobiophysics studies based on surface physics techniques have reached a stage of maturity.

Recent instrumentation advances have made it possible to apply experimental synchrotron radiation techniques of materials science to biophysics problems. We present the first results of a systematic photoelectron spectromicroscopy study of the interaction between metals and neurons in vitro. The main result is that aluminum is not uptaken by granule cells-the most common type of neurons-but it is selectively uptaken by cells such as Purkinje neurons and glial cells. On the contrary, granule cells are capable to uptake other metals like Ni and Co.

MnBi has attracted much attention in recent years due to its potential as a rare-earth-free permanent magnet material. It is unique because its coercivity increases with increasing temperature, which makes it a good hard phase material for exchange coupling nanocomposite magnets. MnBi phase is difficult to obtain, partly because the reaction between Mn and Bi is peritectic, and partly because Mn reacts readily with oxygen. MnO formation is irreversible and harmful to magnet performance. In this paper, we report our efforts toward developing MnBi permanent magnets. To date, high purity MnBi (>90%) can be routinely produced in large quantities. The produced powder exhibits 74.6 emu g(-1) saturation magnetization at room temperature with 9 T applied field. After proper alignment, the maximum energy product (BH)max of the powder reached 11.9 MGOe, and that of the sintered bulk magnet reached 7.8 MGOe at room temperature. A comprehensive study of thermal stability shows that MnBi powder is stable up to 473 K in air.

Stoichiometric epitaxial LaAlO(3) grown on TiO(2)-terminated SrTiO(3)(001) by off-axis pulsed laser deposition is shown to exhibit strong cation intermixing. This result is corroborated by classical and quantum mechanical calculations of the relative stabilities of abrupt and intermixed interface configurations. The valence band offset was measured to be 0.16 ± 0.10 eV, and this value cannot be accounted for theoretically without including intermixing in the physical description of the interface.

Epitaxial thin films of cobalt-doped ZnO (Co : ZnO) were deposited by pulsed laser deposition (PLD) on both c-plane and r-plane sapphire (Al2 O3). The films exhibited high structural quality with narrow x-ray diffraction (XRD) rocking curve peak widths. X-ray absorption spectroscopy (XANES and EXAFS) confirmed well-ordered Co substitution for Zn in ZnO without the formation of secondary phases. A wide range of n-type conductivities (10−4–105 Ω cm) was achieved by controlling the deposition conditions, post-annealing in vacuum, and/or addition of Al during deposition. Despite the high structural quality of the Co : ZnO thin films, no significant room temperature ferromagnetism was observed under any processing or treatment conditions. The lack of ferromagnetism indicates that itinerant conduction band electrons alone are not sufficient to induce ferromagnetism in Co : ZnO, even when the carrier concentration is a significant fraction of the magnetic dopant concentration. The implications of this observation are discussed.

Co doped TiO2-anatase is a promising candidate for a room-temperature ferromagnetic semiconductor. XAFS measurements have been used to investigate the local Co environment and Co valence for several Co-anatase films. The samples were grown on LaAlO3 (001) by oxygen plasma assisted molecular beam epitaxy and on SrTiO3 by atomic oxygen assisted MBE. Co concentrations were about 5%. The measurements were made at the PNC-CAT bending magnet and undulator beamlines at the Advanced Photon Source. For the films on LaAlO3, the near edge clearly shows the presence of only Co(2+), and no evidence for metallic Co, while the films on SrTiO3 showed significant metallic Co. Analysis of the extended fine structure for the LaAlO3 films finds that the Co substitutes for Ti with some distortion of the lattice. Both in-plane and out-of-plane Co–O bonds are expanded from the Ti–O bonds in anatase. The in-plane bonds are expanded approximately twice as much. A deficit in the oxygen coordination number suggests a correlation of oxygen vacancies with Co sites.