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Title: Composition‐Dependent Ferroelectricity of LuFeO 3 Orthoferrite Thin Films
Abstract This work characterizes the structural, magnetic, and ferroelectric properties of epitaxial LuFeO3orthoferrite thin films with different Lu/Fe ratios. LuFeO3thin films are grown by pulsed laser deposition on SrTiO3substrates with Lu/Fe ratio ranging from 0.6 to 1.5. LuFeO3is antiferromagnetic with a weak canted moment perpendicular to the film plane. Piezoresponse force microscopy imaging and switching spectroscopy reveal room temperature ferroelectricity in Lu‐rich and Fe‐rich films, whereas the stoichiometric film shows little polarization. Ferroelectricity in Lu‐rich films is present for a range of deposition conditions and crystallographic orientations. Positive‐up‐negative‐down ferroelectric measurements on a Lu‐rich film yield ≈13 µC cm−2of switchable polarization, although the film also shows electrical leakage. The ferroelectric response is attributed to antisite defects analogous to that of Y‐rich YFeO3, yielding multiferroicity via defect engineering in a rare earth orthoferrite.  more » « less
Award ID(s):
2132623
PAR ID:
10491372
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Electronic Materials
Volume:
9
Issue:
7
ISSN:
2199-160X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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