Investigation of structural,magnetic and optical properties of rare earth substituted bismuth ferrite  

作　　者：T.Durga Rao T.Karthik Saket Asthana 

机构地区：[1]Advanced Functional Materials Laboratory,Department of Physics,Indian Institute of Technology Hyderabad [2]Department of Materials Science and Engineering,Indian Institute of Technology Hyderabad

出　　处：《Journal of Rare Earths》2013年第4期370-375,共6页稀土学报（英文版）

基　　金：supported by Department of Science and Technology (DST),Government of India under Fast Track Scheme (SR/FTP/PS-065/2011)

摘　　要：Polycrystalline BiFeO3 and rare earth substituted Bio.gRo.lFeO3 （BRFO, R=Y, Ho and Er） compounds were prepared by rapid solid state sintering technique. Structural phase analysis indicated that all the compounds stabilized in rhombohedral structure （R3c space group） and a small orthorhombic phase fraction was observed in BRFO compounds. From the Raman spectra results, the changes in the phonon frequencies （A1） and line widths suggested lattice distortion in the BRFO compounds as was evidenced in the XRD analysis. Compared to the linear variation of magnetization with magnetic field （M-H） shown by BFO, an obvious M-H loop was observed in BRFO compounds which could be due to the suppression of space modulated spin structure and was explained on the basis of weak ferromagnetism and field induced spin reorientation. UV-Vis spectroscopy evidenced a change in local FeO6 envi- ronment due to shift in the 6Alg→4T2g energy transition band. BRFO compounds with improved remnant magnetization and coercive field are applicable for magnetoelectric devices.Polycrystalline BiFeO3 and rare earth substituted Bio.gRo.lFeO3 （BRFO, R=Y, Ho and Er） compounds were prepared by rapid solid state sintering technique. Structural phase analysis indicated that all the compounds stabilized in rhombohedral structure （R3c space group） and a small orthorhombic phase fraction was observed in BRFO compounds. From the Raman spectra results, the changes in the phonon frequencies （A1） and line widths suggested lattice distortion in the BRFO compounds as was evidenced in the XRD analysis. Compared to the linear variation of magnetization with magnetic field （M-H） shown by BFO, an obvious M-H loop was observed in BRFO compounds which could be due to the suppression of space modulated spin structure and was explained on the basis of weak ferromagnetism and field induced spin reorientation. UV-Vis spectroscopy evidenced a change in local FeO6 envi- ronment due to shift in the 6Alg→4T2g energy transition band. BRFO compounds with improved remnant magnetization and coercive field are applicable for magnetoelectric devices.

关 键 词：structural distortion SPIN-REORIENTATION G-type antiferromagnet rare earths 

分 类 号：O611.4[理学—无机化学]