Large magnetoresistance induced by surface ferromagnetism in A-type antiferromagnetic La0.4Sr0.6MnO3 nanoparticles
Large magnetoresistance induced by surface ferromagnetism in A-type antiferromagnetic La0.4Sr0.6MnO3 nanoparticles
复制标题
A型反铁磁La0.4Sr0.6MnO3纳米粒子表面铁磁性引起的大磁阻
DOI：
10.1016/j.jmmm.2009.01.013
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发表时间：
2009-07
影响因子：
2.7
通讯作者：
中科院分区：
文献类型：
--
作者：
研究了重掺Sr的A型反铁磁La0. 4Sr0. 6MnO3陶瓷的磁性和输运性质的晶粒尺寸效应。结果表明，随着晶粒尺寸的减小，由于表面键断裂，可以引入表面铁磁性。随着晶粒尺寸的减小，表面铁磁性增强，从Arrott图上区分的相变顺序为第二顺序。从输运性质判断，表面诱导铁磁性是绝缘的。随着晶粒尺寸的减小，高磁场和低磁场下的磁电阻都有很大的提高。在500Oe磁场下，晶粒尺寸为150nm的样品在10、100、200和300K时的磁电阻分别从0.2%、0.1%、0.03%和0.02%提高到晶粒尺寸为20nm的样品在10、100、200和300K时的3%、2.3%、0.43%和0.12%。20万和30万有趣的是，在A型反铁磁La0. 4Sr0. 6MnO3纳米颗粒中，由于表面的铁磁性，可以诱导出较大的磁电阻，这表明在纳米结构的A型反铁磁材料中寻找具有相对较高低场磁电阻的锰氧化物是可能的.
Grain size effects on magnetic and transport properties for heavily Sr-doped A-type antiferromagnetic La0.4Sr0.6MnO3ceramics were studied. It was observed that with decrease in grain size, surface ferromagnetism could be introduced due to bond-breaking at surfaces. With decrease in grain size, the surface ferromagnetism was enhanced, and the phase transition order distinguished from the Arrott plot was a second one. The surface-induced ferromagnetism was insulating as judged from transport properties. With decrease in grain size, magnetoresistance was largely improved for both high magnetic and low magnetic fields. Under a 500Oe magnetic field, the magnetoresistance is improved from 0.2%, 0.1%, 0.03% and 0.02% for the sample with grain size of 150nm at 10, 100, 200 and 300K, respectively, to 3%, 2.3%, 0.43% and 0.12% for the sample with grain size of 20nm at 10, 100, 200 and 300K. It was interesting to find that large magnetoresistance could be induced due to the surface ferromagnetism in A-type antiferromagnetic La0.4Sr0.6MnO3nanoparticles, which suggested that it was possible to search for manganites with relatively high low-field magnetoresistance in nanostructured A-type antiferromagnetic materials.
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影响因子：
3.7
作者：
Y. Moritomo;T. Akimoto;A. Nakamura;K. Ohoyama;M. Ohashi
通讯作者：
Y. Moritomo;T. Akimoto;A. Nakamura;K. Ohoyama;M. Ohashi
影响因子：
3.7
作者：
A. Biswas;I. Das
通讯作者：
A. Biswas;I. Das
DOI：
10.1103/physrevb.62.6437
发表时间：
2000-05
期刊：
arXiv: Materials Science
影响因子：
--
作者：
Pablo Levy;F. Parisi;G. Polla;D. Vega;G. Leyva;H. Lanza;Rafael S. Freitas;L. Ghivelder
通讯作者：
Pablo Levy;F. Parisi;G. Polla;D. Vega;G. Leyva;H. Lanza;Rafael S. Freitas;L. Ghivelder
影响因子：
3.7
作者：
A. Szewczyk;M. Gutowska;B. Dabrowski
通讯作者：
A. Szewczyk;M. Gutowska;B. Dabrowski
影响因子：
3.7
作者：
B. Hattink;M. G. D. Muro;Z. Konstantinović;X. Batlle;A. Labarta;M. Varela
通讯作者：
B. Hattink;M. G. D. Muro;Z. Konstantinović;X. Batlle;A. Labarta;M. Varela