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Epitaxial thin films of cobalt ferrite (CoFe2O4) are grown on two isostructural substrates, (001)-oriented MgGa2O4and ZnGa2O4, using pulsed laser deposition. The substrates have a lattice mismatch of 1.26% and 0.70% with bulk CoFe2O4(CFO) crystal. We have systematically investigated the structural and magnetic properties of the epitaxial CFO films on these substrates. X-ray diffraction and transmission electron microscopy result analysis reveal that the films deposited on spinel ZnGa2O4are essentially free of defects and are under a small compressive strain, while films on MgGa2O4show partial strain relaxation along with defect formation. Room temperature magnetization data indicate that CFO grown on ZnGa2O4substrates have a bulk-like saturation magnetization of 420 emu/cc and a uniaxial substrate-induced anisotropy value of [Formula: see text] [Formula: see text] erg/cm3with an anisotropy field as low as 60 kOe.
- Publication Date:
- NSF-PAR ID:
- Journal Name:
- Applied Physics Letters
- Page Range or eLocation-ID:
- Article No. 102401
- American Institute of Physics
- Sponsoring Org:
- National Science Foundation
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