Spin-lattice-charge coupling in quasi-one-dimensional spin-chain NiTe₂O₅

Authors

Ajay Tiwari; D. Chandrasekhar Kakarla; Gennevieve Macam; Chia-Hsiu Hsu; Feng-Chuan Chuang; H. C. Wu; T. W. Kuo; Arkadeb Pal; H. Chou; D. P. Gulo; H. L. Liu; Y. C. Chuang; Y. C. Lai; C. A. Lee; Mitch M. C. Chou; H. D. Yang

Source

Phys. Rev. Mater. 6, 044409 (2022). DOI: 10.1103/PhysRevMaterials.6.044409

Abstract

A high-quality NiTe₂O₅ single crystal was grown via the flux method and characterized using synchrotron x-ray diffraction (XRD) and electron probe microscopy techniques. The dc magnetization (M) confirms the antiferromagnetic long-range ordering temperature (TN) at 28.5 K. An apparent domelike dielectric anomaly near TN, with scaling of magnetodielectric (MD) coupling with magnetization (MD% ∝ M²), signifies higher-order magnetoelectric (ME) coupling. The critical finding is that magnetoelastic coupling plays a pivotal role in bridging the electrical and magnetic dipoles, which was further confirmed by temperature-dependent XRD. In addition, the theoretical charge density difference maps indicate that the emergence of electrical dipoles between the Ni and O atoms below TN originates through p-d hybridization. Thus, the p-d hybridization-induced magnetoelastic coupling is considered a possible mechanism for the higher-order ME effect in this quasi-onedimensional spin-chain NiTe₂O₅.