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Title: Structural and magnetic properties of CoFe2O4 thin films grown on isostructural lattice-matched substrates

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.

 
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NSF-PAR ID:
10370754
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
10
ISSN:
0003-6951
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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