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This content will become publicly available on September 1, 2026

Title: Room temperature ferroelectricity and self-biased magnetoelectricity in SmFeO3 nanocomposite by 3D strain engineering
Tuning spin and charge degrees of freedom of complex oxide materials can enable significant advancements in future spintronics. In this study, by three dimensional strain engineering, we demonstrate room temperature ferroelectricity and magnetoelectricity in a vertically aligned nanocomposite thin film structure, composed of vertical nanopillars of SmFeO3 (SFO) embedded within the NiFeO4 (NFO) matrix. A three-dimensional tensile strain is induced in the SFO as a result of the unique film architecture. The tensile strain in SFO produces strong room temperature ferroelectric response instead of the normally very weak ferroelectricity of unstrained SFO, which is an improper ferroelectric. The induced ferroelectricity in SFO enables self-biased magnetoelectric coupling to be achieved between the two phases (magnetoelectric coupling coefficient ∼4 × 10−11 sm−1 at room temperature). The magnetoelectric coupling is facilitated by strain transfer across the vertical interfaces of the two phases. We additionally observe an exchange bias of ∼200 Oe (at 2 K) surviving up to the room temperature, indicating strongly coupled interfaces of SFO and NFO. These findings represent a step forward in future magnetoelectric RAM devices.  more » « less
Award ID(s):
2323752
PAR ID:
10635089
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
APL Electronic Devices
Volume:
1
Issue:
3
ISSN:
2995-8423
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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