Exchange-Interaction-Like Behavior in Ferroelectric Bilayers

Pravin Kavle; Aiden M Ross; Jacob A Zorn; Piush Behera; Eric Parsonnet; Xiaoxi Huang; Ching-Che Lin; Lucas Caretta; Long-Qing Chen; Lane W Martin

doi:10.1002/adma.202301934

Exchange-Interaction-Like Behavior in Ferroelectric Bilayers

Adv Mater. 2023 Sep;35(39):e2301934. doi: 10.1002/adma.202301934. Epub 2023 Jul 23.

Authors

Pravin Kavle^{1

2}, Aiden M Ross³, Jacob A Zorn³, Piush Behera^{1

2}, Eric Parsonnet⁴, Xiaoxi Huang^{1

2}, Ching-Che Lin^{1

2}, Lucas Caretta^{5

2

6}, Long-Qing Chen³, Lane W Martin^{1

2}

Affiliations

¹ Department of Materials Science and Engineering, University of California, Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
² Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
³ Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA.
⁴ Department of Physics, University of California, Berkeley, CA, 94720, USA.
⁵ Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA.
⁶ School of Engineering, Brown University, Providence, RI, 02912, USA.

PMID: 37294272
DOI: 10.1002/adma.202301934

Abstract

Interlayer coupling in materials, such as exchange interactions at the interface between an antiferromagnet and a ferromagnet, can produce exotic phenomena not present in the parent materials. While such interfacial coupling in magnetic systems is widely studied, there is considerably less work on analogous electric counterparts (i.e., akin to electric "exchange-bias-like" or "exchange-spring-like" interactions between two polar materials) despite the likelihood that such effects can also engender new features associated with anisotropic electric dipole alignment. Here, electric analogs of such exchange interactions are reported, and their physical origins are explained for bilayers of in-plane polarized Pb_1-x Sr_x TiO₃ ferroelectrics. Variation of the strontium content and thickness of the layers provides for deterministic control over the switching properties of the bilayer system resulting in phenomena analogous to an exchange-spring interaction and, leveraging added control of these interactions with an electric field, the ability to realize multistate-memory function. Such observations not only hold technological promise for ferroelectrics and multiferroics but also extend the similarities between ferromagnetic and ferroelectric materials to include the manifestation of exchange-interaction-like phenomena.

Keywords: exchange bias; exchange springs; ferroelectrics; multistate; thin films.

Abstract

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