功能材料
功能材料
공능재료
JOURNAL OF FUNCTIONAL MATERIALS
2014年
1期
1139-1142
,共4页
张正明%曹庆琪%王敦辉%都有为
張正明%曹慶琪%王敦輝%都有為
장정명%조경기%왕돈휘%도유위
磁场退火%磁电阻%自旋极化输运
磁場退火%磁電阻%自鏇極化輸運
자장퇴화%자전조%자선겁화수운
magnetic annealing%magnetoresistance%spin-polarized tunneling
为了提高 La0.7 Sr0.3 MnO 3的低场磁电阻效应,将样品进行了磁场退火处理.实验结果表明,磁场退火并没有改变样品的磁矩,但对其磁各向异性产生了较大的影响.与零磁场下退火的样品相比,磁场退火样品的磁电阻明显提高.这种增强效应在低磁场下更加明显,在0.1 T 的外磁场下,磁退火样品的磁电阻比零场退火的提高了140%.利用自旋极化隧穿机制解释了这种增强的磁电阻效应.
為瞭提高 La0.7 Sr0.3 MnO 3的低場磁電阻效應,將樣品進行瞭磁場退火處理.實驗結果錶明,磁場退火併沒有改變樣品的磁矩,但對其磁各嚮異性產生瞭較大的影響.與零磁場下退火的樣品相比,磁場退火樣品的磁電阻明顯提高.這種增彊效應在低磁場下更加明顯,在0.1 T 的外磁場下,磁退火樣品的磁電阻比零場退火的提高瞭140%.利用自鏇極化隧穿機製解釋瞭這種增彊的磁電阻效應.
위료제고 La0.7 Sr0.3 MnO 3적저장자전조효응,장양품진행료자장퇴화처리.실험결과표명,자장퇴화병몰유개변양품적자구,단대기자각향이성산생료교대적영향.여령자장하퇴화적양품상비,자장퇴화양품적자전조명현제고.저충증강효응재저자장하경가명현,재0.1 T 적외자장하,자퇴화양품적자전조비령장퇴화적제고료140%.이용자선겁화수천궤제해석료저충증강적자전조효응.
Polycrystalline perovskite La0.7 Sr0.3 MnO 3 was annealed under magnetic field in order to increase the low-field magnetoresistance effect.The experimental results show that the magnetic annealing would not affect the magnetic moments but remarkably change the magnetic anisotropy of the sample.Compared with the per-ovskite without magnetic annealing,the magnetic-annealed La0.7 Sr0.3 MnO 3 exhibits large magnetoresistance effect,which can be more obviously observed in low magnetic field.At room temperature,a 140% enhancement of magnetoresistance response at 0.1 T was observed in the magnetic-annealed sample,which can be explained with the mechanism of spin-polarized intergrain tunneling.