Epitaxial thin films of cobalt ferrite (CoFe2O4) are grown on two isostructural substrates, (001)-oriented MgGa2O4 and 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 ZnGa2O4 are essentially free of defects and are under a small compressive strain, while films on MgGa2O4 show partial strain relaxation along with defect formation. Room temperature magnetization data indicate that CFO grown on ZnGa2O4 substrates have a bulk-like saturation magnetization of 420 emu/cc and a uniaxial substrate-induced anisotropy value of −22.9× 106 erg/cm3 with an anisotropy field as low as 60 kOe.
- Award ID(s):
- 1952957
- PAR ID:
- 10504117
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- ACS Applied Nano Materials
- Volume:
- 6
- Issue:
- 13
- ISSN:
- 2574-0970
- Page Range / eLocation ID:
- 10986 to 11000
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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