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Single-phase CrO 2 nanostructured thin films have been grown directly on MgO͑100͒ by pulsed laser ablation of a metallic Cr target in an O 2 environment. X-ray diffraction shows that these films are strained and consist of CrO 2 crystallites with two possible epitaxial relationships to the substrate; either CrO 2 ͑110͒ or CrO 2 ͑200͒ is parallel to MgO͑100͒. Scanning electron microscopy and atomic force microscopy reveal orthogonally arranged nanoneedles and platelike structures ͑both 30-50 nm thick͒. X-ray photoemission confirms that the films are primarily CrO 2 covered with a thin CrO 3 overlayer and indicates its complete synthesis without any residual metallic Cr.

The field electron emission (FEE) properties of nitrogen-incorporated nanocrystalline diamond films were enhanced due to Li-ion implantation/annealing processes. Li-ion implantation mainly induced the formation of electron trap centers inside diamond grains, whereas post-annealing healed the defects and converted the a-C phase into nanographite, forming conduction channels for effective transport of electrons. This resulted in a high electrical conductivity of 11.0 S/cm and enhanced FEE performance with a low turn-on field of 10.6 V/lm, a high current density of 25.5 mA/cm 2 (at 23.2 V/lm), and a high lifetime stability of 1,090 min for nitrogen incorporated nanocrystalline diamond films. Published by AIP Publishing.

FeMoO 6 films have been grown on a Si͑100͒ substrate by pulsed laser deposition under different growth conditions including deposition temperature and time. A nanocrystalline single-phase Sr 2 FeMoO 6 film was obtained at a temperature as low as 600°C. This high-quality ferromagnetic film was found to have a saturation magnetic moment of 3.4 B per formula unit and a coercive field of 1.5 kOe at 77 K with micrometer-sized magnetic domains. By using glancing-incidence x-ray diffraction with different incident beam angles, the crystal structure of the film was sampled as a function of depth. For the as-grown Sr 2 FeMoO 6 films thicker than 60 nm, a preferential orientation of the nanocrystals in the film was observed, despite the lack of good lattice matching with the Si substrate. At a higher deposition temperature of 800°C, the as-grown film exhibited the same saturation magnetic moment but with a discernibly lower coercive field of 0.8 kOe, consistent with the larger grain size obtained at a higher growth temperature.

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