مرکز منطقه ای اطلاع رساني علوم و فناوري - Dielectric Permittivity and Magnetoelectric Coupling in Multiferroic <formula formulatype="inline"> <img src="/images/tex/19907.gif" alt="{\\hbox {BiFeO}}_{3}"> </formula> and <formula formulatype="inline"> <img src="/images/tex/19947.gif" alt="({\\hbox {

Title :

Dielectric Permittivity and Magnetoelectric Coupling in Multiferroic ${\\hbox {BiFeO}}_{3}$ and $({\\hbox {</div> </div> <div class='row'> <div class='leftDiv labelDiv col-xs-4 col-sm-2 fullRecLabelEnglish'>Author : </div><div class='valueDiv leftDirection leftAlign col-xs-8 col-sm-10 fullRecValueEnglish'>Tu, C.-S. ; Ding, Yi ; Yang, Wen-Cheng ; Wang, T.H. ; Chien, R.R. ; Schmidt, V. Hugo ; Yao, Y.D. ; Wu, K.T.</div> </div> <div class='row'> <div class='leftDiv labelDiv col-xs-4 col-sm-2 fullRecLabelEnglish'>Author_Institution : </div><div class='valueDiv leftDirection leftAlign col-xs-8 col-sm-10 fullRecValueEnglish'>Grad. Inst. of Appl. Sci. & Eng., Fu Jen Catholic Univ., Taipei, Taiwan</div> </div> <div class='row'> <div class='leftDiv labelDiv col-xs-4 col-sm-2 fullRecLabelEnglish'>Volume : </div><div class='valueDiv leftDirection leftAlign col-xs-8 col-sm-10 fullRecValueEnglish'>47</div> </div> <div class='row'> <div class='leftDiv labelDiv col-xs-4 col-sm-2 fullRecLabelEnglish'>Issue : </div><div class='valueDiv leftDirection leftAlign col-xs-8 col-sm-10 fullRecValueEnglish'>10</div> </div> <div class='row'> <div class='leftDiv labelDiv col-xs-4 col-sm-2 fullRecLabelEnglish'>fYear : </div><div class='valueDiv leftDirection leftAlign col-xs-8 col-sm-10 fullRecValueEnglish'>2011</div> </div> <div class='row'> <div class='leftDiv labelDiv col-xs-4 col-sm-2 fullRecLabelEnglish'>Firstpage : </div><div class='valueDiv leftDirection leftAlign col-xs-8 col-sm-10 fullRecValueEnglish'>3343</div> </div> <div class='row'> <div class='leftDiv labelDiv col-xs-4 col-sm-2 fullRecLabelEnglish'>Lastpage : </div><div class='valueDiv leftDirection leftAlign col-xs-8 col-sm-10 fullRecValueEnglish'>3346</div> </div> <div class='row'> <div class='leftDiv labelDiv col-xs-4 col-sm-2 fullRecLabelEnglish'>Abstract : </div><div class='valueDiv leftDirection leftAlign col-xs-8 col-sm-10 fullRecValueEnglish'>Dielectric permittivity and loss of BiFeO<sub>3</sub> (BFO) and 5 mol% lanthanum-substituted BFO [(Bi<sub>0.95</sub>La<sub>0.05</sub>)FeO<sub>3</sub> or BFO-5% La] ceramics have been carried out as functions of temperature and frequency. A frequency-dependent and broad dielectric shoulder and maximum were observed in BFO and BFO-5% La near 600-700 K. These dielectric responses are likely due to the magnetoelectric coupling while the antiferromagnetic-paramagnetic transition takes place near the Néel temperature. As an approximation, a barrier model with intrinsic barriers B (in temperature unit) every lattice constant <i>a</i> and extrinsic barriers B +Δ every distance <i>d</i> is introduced to describe the low-frequency upturn in dielectric loss in the high-temperature region. Good qualitative fits are obtained for BFO and BFO-5% La. This work suggests that 5 mol% La substitution can enhance dielectric response and considerably reduce electric conductivity.</div> </div> <div class='row'> <div class='leftDiv labelDiv col-xs-4 col-sm-2 fullRecLabelEnglish'>Keywords : </div><div class='valueDiv leftDirection leftAlign col-xs-8 col-sm-10 fullRecValueEnglish'>Neel temperature; bismuth compounds; dielectric losses; electrical conductivity; ferroelectric ceramics; lanthanum compounds; lattice constants; magnetoelectric effects; multiferroics; paramagnetic-antiferromagnetic transitions; permittivity; (Bi<sub>0.95</sub>La<sub>0.05</sub>)FeO<sub>3</sub>; BiFeO<sub>3</sub>; Neel temperature; antiferromagnetic-paramagnetic transition; barrier model; dielectric loss; dielectric permittivity; electrical conductivity; high-temperature region; lattice constants; magnetoelectric coupling; multiferroic ceramics; temperature 600 K to 700 K; Bismuth; Ceramics; Conductivity; Dielectric losses; Iron; Magnetoelectric effects; <formula formulatype=$ $({hbox {Bi}}_{0.95}{hbox {La}}_{0.05}){hbox {FeO}}_{3}$; ${hbox {BiFeO}}_{3}$; Barrier model; dielectric permittivity; magnetoelectric coupling;