Magnetoelectric coupling and structural phase transition in MnTiO3 single crystal
Abstract
This work presents a systematic investigation of magnetoelectric (ME) coupling in high-quality MnTiO3 single crystals, a prototypical geometrically frustrated antiferromagnet. X-ray diffraction confirms a pure hexagonal structure with excellent crystallinity. A paramagnetic to antiferromagnetic transition is observed at TN ∼ 64 K, exhibiting significant magnetic anisotropy. The key finding is the direct evidence of bidirectional magnetoelectric coupling: An applied magnetic field induces a sharp anomaly in the c-axis dielectric constant near TN, while an electric field effectively modulates the magnetization. Specific heat and thermal strain measurements reveal a concomitant structural distortion (a-axis contraction and c-axis elongation) at TN. Crucially, this distortion is field-independent, ruling out magnetostriction. Our results demonstrate that the magnetoelectric coupling is cooperatively driven by the antiferromagnetic order and the structural phase transition, consistent with spin-lattice coupling or exchange striction mechanisms. This work provides critical insights for the design of multiferroic materials.
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (17)
Ping Bao
Gangtao Li
School of Physics and Electronic Engineering, Qujing Normal University 2 , Qujing 655011,
Qi Chen
Yanru Kang
School of Physics and Electronic Engineering, Qujing Normal University 2 , Qujing 655011,
Zeshan Liu
School of Physics and Electronic Engineering, Qujing Normal University 2 , Qujing 655011,
Fengjun Jiang
School of Physics and Electronic Engineering, Qujing Normal University 2 , Qujing 655011,
Yao Zhao
Guanbing Wang
School of Physics and Electronic Engineering, Qujing Normal University 2 , Qujing 655011,
Hongxing Zhan
School of Physics and Electronic Engineering, Qujing Normal University 2 , Qujing 655011,
Hongwei Liu
The Australian Centre for Microscopy and Microanalysis
Shengxian Wei
School of Physics and Electronic Engineering, Qujing Normal University 2 , Qujing 655011,
Yuanlei Zhang
School of Physics and Electronic Engineering, Qujing Normal University 2 , Qujing 655011,
Zhe Li
Zhen Qian
Kun Xu
College of Chemistry and Life Science
Tian Gao
State Key Laboratory of Special Materials Surface Engineering, School of Materials Science and Engineering
Yiming Cao
Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University