Polar oxide interface stabilization by formation of metallic nanocrystals

2019-12-24 11:46:38

interface electron nanocrystals oxide magnetite

责任者: Lazarov, V.K.;Chambers, S.A.;Gajdardziska-Josifovska, M. 单位: Dept. of Phys., Univ. of Wisconsin-Milwaukee, Milwaukee, WI, USA 来源出处: Physical Review Letters(Phys. Rev. Lett. (USA)),2003/05/30,90(21):216108-1 摘要: In situ x-ray photoelectron spectroscopy and ex situ transmission electron microscopy and diffraction studies of a model Fe3O4(111)/MgO(111) polar oxide interface exclude stabilization by interface faceting, reconstruction, or by formation of a continuous interfacial layer with altered stoichiometry, and uncover stabilization by dominant formation of metallic Fe(110) nanocrystals. The iron nanocrystals nucleate both at the interface and within the magnetite film and grow in a Nishiyama-Wasserman orientation relationship with a bimodal size distribution related to twinning. Minority magnetite nanocrystals were also observed, growing in the less polar (100) orientation than the magnetite (111) film. Electron transfer and bond hybridization mechanisms are likely at the metal/oxide and oxide/oxide interfaces and remain to be explored 关键词: electron diffraction;interface structure;iron compounds;magnesium compounds;magnetic epitaxial layers;molecular beam epitaxial growth;nanostructured materials;reflection high energy electron diffraction;surface energy;transmission electron microscopy;twinning;X-ray photoelectron spectra;Fe3O4(111)/MgO(111) polar oxide interface stabilization;metallic Fe(110) nanocrystal formation;in situ x-ray photoelectron spectroscopy;ex situ transmission electron microscopy;nanocrystal nucleation;magnetite film;Nishiyama-Wasserman orientation relationship;bimodal size distribution;twinning;minority magnetite nanocrystals;electron transfer mechanisms;bond hybridization mechanisms;RHEED;CBED;surface energetics;molecular beam epitaxy;Fe3O4-MgO;Fe