摘要
采用熔盐法,以Bi_(2)O_(3)为自助溶剂,成功制备了Sr/Ti∶BiFeO_(3)系列晶体。X射线衍射谱和Rietveld精修结果显示,Sr^(2+)、Ti^(4+)离子掺杂使BiFeO_(3)的结构从三方相转变为无双折射的立方相。这一结构转变也通过扫描电子显微镜的观察得到了证实。Sr/Ti∶BiFeO_(3)的X射线光电子能谱表明,随着Sr^(2+)、Ti^(4+)的引入,BiFeO_(3)的Fe元素价态发生改变。高价Fe离子的生成使BiFeO_(3)产生晶格畸变,并对其周期性螺旋自旋磁结构产生抑制作用,从而使BiFeO_(3)的宏观磁性得到提高,但矫顽力没有发生明显变化。晶体磁滞回线和磁圆二色效应光谱显示,Bi_(0.7)Sr_(0.3)Fe_(0.7)Ti_(0.3)O_(3)的饱和磁化强度较BiFeO_(3)提高了3倍,其磁光效应达到商用Y_(3)Fe_(5)O_(12)的4.5倍。
Objective Magneto-optical crystals are pivotal components that determine the performance of magneto-optical devices.Through the hybridization between the excited Bi^(3+) 6p orbital and Fe^(3+) 3d orbital, the modification of superexchange induces a strong mixing between crystal field states of varying energies, greatly enhancing the magneto-optic effect in ferrite. Doping Bi^(3+) ions emerges as a key approach to enhancing the magneto-optical properties of commercial Y_(3)Fe_(5)O_(12)(YIG) crystals. However, despite being the only known room temperature single-phase multiferroic material, there is scarce literature reporting on the magneto-optical properties and its applications in magneto-optical devices of the perovskite BiFeO_(3) with a high concentration of Bi^(3+). This can be attributed to its unique spiral G-type antiferromagnetic structure, which exhibits weak macroscopic magnetism. Additionally, due to its trigonal crystal system and birefringence effect, BiFeO_(3) demonstrates a considerably feeble magneto-optical effects. In the present study, stable pure phase cubic BiFeO_(3) single crystals are grown by doping Sr^(2+) and Ti^(4+) ions. This eliminates the birefringence effect of the trigonal BiFeO_(3) and induces strong magnetic and magneto-optical effects, providing a useful reference for exploring high-quality,large-size new magneto-optical crystals suitable for high-performance magneto-optical devices.Methods Bi_(2)O_(3) is chosen as the self-flux solvent, and a series of crystals including Bi1-xSrxFeO_(3) and Bi_(1-x)Sr_(x)Fe_(1-x)Ti_(x)O_(3)(x=0-0.5) are grown by using the molten salt method. The crystal structure and lattice parameters of Sr∶BiFeO_(3) and Sr/Ti∶BiFeO_(3) are determined by XRD spectra analysis and Rietveld refinement. The structure and morphology changes of BiFeO_(3) crystals are observed by scanning electron microscopy(SEM). Elemental valence states in the crystals are analyzed using X-ray photoelectron spectroscopy(XPS), while magnetic properties and magneto-optical perfor
作者
林楠茜
杨新攀
许晨浚
吴华钦
张宏
庄乃锋
胡晓琳
Lin Nanxi;Yang Xinpan;Xu Chenjun;Wu Huaqin;Zhang Hong;Zhuang Naifeng;Hu Xiaolin(Key Laboratory of Non-destructive Testing Technology,Fujian Province University,Fujian Polytechnic Normal University,Fuqing 350300,Fujian,China;College of Chemistry,Fuzhou University,Fuzhou 350108,Fujian,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2024年第14期181-190,共10页
Acta Optica Sinica
基金
国家自然科学基金(62105063)
福建省自然科学基金(2021J05271,2022J0123)
福建省中青年教师教育科研项目(JAT201373)。
关键词
材料
熔盐法
磁光晶体
磁圆二色性
BiFeO_(3)
磁性
materials
molten salt method
magneto-optical crystal
magnetic circular dichroism
BiFeO_(3)
magnetism
