Experimental Evidence of the Origin of Nanophase Separation in Low Hole-Doped Colossal Magnetoresistant Manganites

被引：4

作者：

Cortes-Gil, Raquel ^{[1
]}

Luisa Ruiz-Gonzalez, M. ^{[1
]}

Gonzalez-Merchante, Daniel ^{[1
]}

Alonso, Jose M. ^{[2
,3
]}

Hernando, Antonio ^{[2
,4
]}

Trasobares, Susana ^{[5
]}

Vallet-Regi, Maria ^{[6
]}

Rojo, Juan M. ^{[7
]}

Gonzalez-Calbet, Jose M. ^{[1
,2
]}

机构：

[1] Univ Complutense Madrid, Fac Quim, Dept Quim Inorgan, CEI Moncloa, E-28040 Madrid, Spain

[2] UCM CSIC ADIF, Inst Magnetismo Aplicado, Madrid 28230, Spain

[3] CSIC, Inst Ciencia Mat, E-28049 Madrid, Spain

[4] UCM, CEI Moncloa, Fac Fis, Dept Fis Mat, Madrid 28040, Spain

[5] Univ Cadiz, Fac Ciencias, Dept Ciencia Mat & Ingn Met & Quim Inorgan, Cadiz 11510, Spain

[6] UCM, CIBER Bioingn Biomat & Nanomed CIBER BBN, Fac Farm, Dept Quim Inorgan & Bioinorgan, Madrid 28040, Spain

[7] IMDEA Nanosci, Madrid 28049, Spain

来源：

NANO LETTERS | 2016年 / 16卷 / 01期

关键词：

Nanophase segregation; atomic resolution; magnetoresistance; manganites; PHASE; TRANSITION; MANGANESE;

D O I：

10.1021/acs.nanolett.5b04704

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

While being key to understanding their intriguing physical properties, the origin of nanophase separation in manganites and other strongly correlated materials is still unclear. Here, experimental evidence is offered for the origin of the controverted phase separation mechanism in the representative La1-xCaxMnO3 system. For low hole densities, direct evidence of Mn4+ holes localization around Ca2+ ions is experimentally provided by means of aberration-corrected scanning transmission electron microscopy combined with electron energy loss spectroscopy. These localized holes give rise to the segregated nanoclusters, within which double exchange hopping between Mn3+ and Mn4+ remains restricted, accounting for the insulating character of perovskites with low hole density. This localization is explained in terms of a simple model in which Mn4+ holes are bound to substitutional divalent Ca2+ ions.

引用

页码：760 / 765

页数：6