磁场诱导的TmFeO3单晶自旋重取向
Magnetic-field-induced spin reorientation in TmFeO3 single crystals
摘要
Abstract
TmFeO3 exhibits rich physical properties such as magneto-optical effect,multiferroicity,and spin reorientation,making it possess significant research value in condensed matter physics and materials science.In this study,we utilize a time-domain terahertz magneto-optical spectroscopy system to investigate the changes in spin resonance frequency of TmFeO3 single crystal at T = 1.6 K under external magnetic fields in a range of 0-7 T.The TmFeO3 sample is grown in an optical floating zone furnace and its crystallographic orientation is determined by using back-reflection Laue X-ray photography with a tungsten target.The measurement setup is a self-built time-domain terahertz magneto-optical spectroscopy system,with magnetic fields in a range of 0-7 T,temperatures in a range of 1.6-300 K,and a spectral range of 0.2-2.0 THz.A pair of 1 mm-thick ZnTe nonlinear crystals is used to generate and detect terahertz signals through optical rectification and electro-optic sampling technique.The system variable temperature and magnetic field are controlled by a superconducting magnet.In experiments,a linearly polarized terahertz wave is vertically incident on the sample surface,and its magnetic component HTHz is parallel to the sample surface.By rotating the sample,the angle(θ)between macroscopic magnetic moment M and HTHz can be tuned,achieving selective excitations of the two modes,that is,θ = 0 for q-AFM mode and 90° for q-FM mode.Terahertz absorption spectrum results indicate that as the magnetic field increases,the quasi-ferromagnetic resonance(q-FM)of TmFeO3 single crystal shifts towards high frequencies,and quasi-antiferromagnetic resonance(q-AFM)transits to q-FM under low critical magnetic fields(2.2-3.6 T).Through magnetic structure analysis and theoretical fitting,it is confirmed that the magnetic moment of the single crystal undergoes magnetic field induced spin reorientation.This study is helpful in better understanding of the regulation mechanism of the internal magnetic structure of rare earth ferrite under the combined action of external magnetic field and temperature field,and also in developing related spin electronic devices.关键词
太赫兹/稀土正铁氧体/铁磁共振/自旋重取向Key words
terahertz/rare earth orthoferrite/ferromagnetic resonance/spin reorientation引用本文复制引用
王宁,黄峰,陈盈,朱国锋,苏浩斌,郭翠霞,王向峰..磁场诱导的TmFeO3单晶自旋重取向[J].物理学报,2024,73(1):298-304,7.基金项目
国家自然科学基金(批准号:62105068)、福建省自然科学基金(批准号:2023J05096,2023J01055)、福建省太赫兹功能器件与智能传感重点实验室(福州大学)开放基金(批准号:FPKLTFDIS202304)、CAD/CAM福建省高校工程研究中心开放基金(批准号:K202203)、智能配电网装备福建省高校工程研究中心开放基金(批准号:KFRC202203)、福建省教育厅中青年教师教育科研项目(批准号:JAT220032)和福州大学科研启动项目(批准号:XRC-22073)资助的课题.Project supported by the National Natural Science Foundation of China(Grant No.62105068),the Natural Science Foundation of Fujian Province,China(Grant Nos.2023J05096,2023J01055),the Key Laboratory of Terahertz Functional Devices and Intelligent Sensing of Fujian Province,China(Grant No.FPKLTFDIS202304),the Engineering Research Center for CAD/CAM of Fujian Universities(Grant No.K202203),the Engineering Research Center of Smart Distribution Grid Equipment,China(Grant No.KFRC202203),the Education and Scientific Research Foundation for Young Teachers in Fujian Province,China(Grant No.JAT220032),and the Scientific Research Start-up Project of Fuzhou University,China(Grant No.XRC-22073). （批准号:62105068）
