Physical Review B
covering condensed matter and materials physics
- Highlights
- Recent
- Accepted
- Collections
- Authors
- Referees
- Search
- Press
- About
- Editorial Team
Spin and lattice dynamics in the van der Waals antiferromagnet
Junbo Liao, Zhentao Huang, Yanyan Shangguan, Bo Zhang, Shufan Cheng, Hao Xu, Ryoichi Kajimoto, Kazuya Kamazawa, Song Bao, and Jinsheng Wen
Phys. Rev. B 109, 224411 – Published 7 June 2024
- Article
- References
- No Citing Articles
PDFHTMLExport Citation
Abstract
Antiferromagnetic van der Waals family have attracted significant research attention due to the possibility of realizing long-range magnetic order down to the monolayer limit. Here, we perform inelastic neutron scattering measurements on single-crystal samples of , a member of the family, to study the spin dynamics and determine the effective spin model. The excited magnon bands are well characterized by a spin model, which includes a Heisenberg term with three intraplane exchange parameters (meV, meV, meV) and one interplane parameter (meV), and an easy-plane single-ion anisotropy term (meV). Additionally, we observe the intersection of the magnon and phonon bands but no anomalous spectral features induced by the formation of magnon-phonon hybrid excitations at the intersecting region. We discuss possible reasons for the absence of such hybrid excitations in .
- Received 12 December 2023
- Revised 11 April 2024
- Accepted 24 May 2024
DOI:https://doi.org/10.1103/PhysRevB.109.224411
©2024 American Physical Society
Physics Subject Headings (PhySH)
- Research Areas
Spin dynamics
- Physical Systems
Antiferromagnets
- Techniques
Neutron scattering
Condensed Matter, Materials & Applied Physics
Authors & Affiliations
Junbo Liao1, Zhentao Huang1, Yanyan Shangguan1, Bo Zhang1, Shufan Cheng1, Hao Xu1, Ryoichi Kajimoto2, Kazuya Kamazawa3, Song Bao1,*, and Jinsheng Wen1,4,†
- 1National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China
- 2J-PARC Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan
- 3Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS), Tokai 319-1106, Ibaraki, Japan
- 4Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
- *Contact author: songbao@nju.edu.cn
- †Contact author: jwen@nju.edu.cn
Article Text (Subscription Required)
Click to Expand
References (Subscription Required)
Click to Expand
Issue
Vol. 109, Iss. 22 — 1 June 2024
Access Options
- Buy Article »
- Log in with individual APS Journal Account »
- Log in with a username/password provided by your institution »
- Get access through a U.S. public or high school library »
Images
Figure 1
(a)Top view of the hexagonal structure of in the a-b plane. Arrows indicate the magnetic moments on Mn atoms. Dashed lines indicate the paths for the magnetic exchange interactions. (b)Schematic structures of the primitive cell of . (c)Temperature dependence of the magnetic susceptibility (filled symbols, left axis) and the inverse magnetic susceptibility (open symbols, right axis) with field applied parallel and perpendicular to the -axis. Solid lines and the arrow denote the Curie-Weiss fit of and the Néel transition temperature, respectively. (d)Temperature dependence of the specific heat (circles, left axis) and the integrated intensity of Bragg peak (squares, right axis). Error bars represent one standard deviation. The vertical dashed line indicates the Néel transition temperature. The dashed curve through the integrated intensities is a guide to the eyes.
Figure 2
(a)Measured magnetic Bragg peaks in the plane with the incident energy of meV for . The energy is integrated over meV. The lattice contributions are eliminated by subtracting the data of 150K. (b)Theoretically calculated magnetic Bragg peaks in the plane according to the untwinned case, termed the pattern. (c)Reflection of the pattern about the line, termed the pattern. (d)Superposition of the patterns in (b)and (c), termed the pattern, representing the magnetic Bragg scatterings from the twinned sample.
Figure 3
INS results of the magnetic excitation spectra at 6K along the in-plane (a)and out-of-plane (b)directions. The data were obtained with meV for (a), and meV for (b). In (a), the integration thickness of the other in-plane direction, orthogonal to the high-symmetry path, is chosen to be rlu, and the wave vectors are integrated over [2.5,3.5] rlu. In (b), the integration range for the two orthogonal in-plane vectors is rlu. (c),(d)Calculated in-plane and out-of-plane magnon dispersions using the linear spin-wave theory (LSWT), respectively. The data points are extracted from the experimental spectra presented in (a)and (b). (e),(f) Calculated magnetic excitation spectra, which are superposed with cases taking into account the twinning effect and instrumental resolutions. The inset in (a)illustrates the high-symmetry paths of the in-plane excitation spectra.
Figure 4
(a)Constant- contour at 5meV in the plane, obtained with meV. The integration thickness of the energy is meV. Lines and the oval denote magnon excitations and phonon excitations, respectively. The dashed lines indicate the positions where the magnon and phonon dispersions intersect with each other. (b)The overlapped magnon and phonon excitations at 6K presented in the same momentum-energy window with meV. Triangles and squares denote magnon and phonon dispersions extracted from (c)and (d), respectively. (c),(d)The individual magnon and phonon spectra, obtained with rlu at 6K and rlu at 150K, respectively. The integration thicknesses of the and [001] directions are and rlu, respectively.
Figure 5
(a),(b)Calculated magnon spectra with and without the term, respectively. (c)Comparison between the measured energy distribution of the spectral weight with the calculations with and without the term at .