title: Engineered magnetic shape anisotropy in BiFeO3-CoFe2O4 self-assembled thin films.
abstract: We report growth of various phase architectures of self-assembled BiFeO3-CoFe2O4 (BFO-CFO) thin films on differently oriented SrTiO3 (STO) substrates. CFO forms segregated square, stripe, and triangular nanopillars embedded in a coherent BFO matrix on (001)-, (110)-, and (111)-oriented STO substrates, respectively. Nanostructures with an aspect ratio of up to 5:1 with a prominent magnetic anisotropy were obtained on both (001) and (110) STO along out-of-plane and in-plane directions. Magnetic easy axis rotation from in-plane to out-of-plane directions was realized through aspect ratio control. An intractable in-plane anisotropy was fixed in CFO on (111) STO due to the triangular shape of the ferromagnetic phase nanopillars. These studies established a detailed relationship of magnetic anisotropy with specific shape and dimensions of ordered magnetic arrays. The results suggest a way to effectively control the magnetic anisotropy in patterned ferromagnetic oxide arrays with tunable shape, aspect ratio, and elastic strain conditions of the nanostructures.
authors.affiliation: Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States. zgwang@vt.edu
authors.forename: Zhiguang
authors.initials: Z
authors.lastname: Wang
authors.forename: Yanxi
authors.initials: Y
authors.lastname: Li
authors.forename: Ravindranath
authors.initials: R
authors.lastname: Viswan
authors.forename: Bolin
authors.initials: B
authors.lastname: Hu
authors.forename: Vincent G
authors.initials: VG
authors.lastname: Harris
authors.forename: Jiefang
authors.initials: J
authors.lastname: Li
authors.forename: Dwight
authors.initials: D
authors.lastname: Viehland
mesh_terms: D016880:Anisotropy; D001729:Bismuth / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D005290:Ferric Compounds / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D060526:Magnetic Fields; D008422:Materials Testing; D008567:Membranes, Artificial; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D005290:Ferric Compounds; D046911:Macromolecular Substances; D008567:Membranes, Artificial; C000499:ferric oxide; D003035:Cobalt; D001729:Bismuth