Control of Magnetoelectric Coupling in the Co2Y-Type Hexaferrites

Published

March 16, 2021

Author(s)

Chang B. Park, Kwang W. Shin, Sae H. Chun, Jun H. Lee, Yoon S. Oh, Steven M. Disseler, Colin A. Heikes, William D. Ratcliff, Woo-Suk Noh, Jae-Hoon Park, Kee H. Kim

Abstract

We comprehensively investigated the magnetic, ferroelectric, and ME properties of Ba_2-xSr_xCo₂(Fe_1-yAl_y)₁₂O₂₂ single crystals in broad doping ranges of Sr (1.0 less than or equal to} x less than or equal to} 1.8) and Al (0.00 less than or equal to} y less than or equal to} 0.08). Most of the investigated compounds exhibit an intriguing coexistence of two apparently competing magnetic phases: a transverse conical (TC) and alternating longitudinal conical (ALC) spin structure. The magnetic properties show that the Ba_0.2Sr_1.8Co₂(Fe_0.98Al_0.04)₁₂O₂₂ crystal has the highest ordering temperature and largest volume fraction of the ALC phase at zero H; further, after the application of an in-plane H, it exhibits a maximized volume fraction of the metastable TC phase, resulting in the highest ME susceptibility and electric polarization at all temperatures below 300 K. Our findings demonstrate that securing the thermal stability of the ALC phase is a crucial prerequisite to achieve optimized ME coupling in Co₂Y-type hexaferrites, pointing to a general strategy applicable to other hexaferrites as well

Citation

Physical Review Materials

Volume

5

Issue

3

Pub Type

Journals

Keywords

neutron, magnetism, multiferroic

Citation

Park, C. , Shin, K. , Chun, S. , Lee, J. , Oh, Y. , Disseler, S. , Heikes, C. , Ratcliff, W. , Noh, W. , Park, J. and Kim, K. (2021), Control of Magnetoelectric Coupling in the Co₂Y-Type Hexaferrites, Physical Review Materials (Accessed October 21, 2025)