Correlating material-specific layers and magnetic distributions within onion-like Fe3O4/MnO/γ-Mn2O3 core/shell nanoparticles

被引：25

作者：

Krycka, K. L. ^{[1
]}

Borchers, J. A. ^{[1
]}

Laver, M. ^{[2
]}

Salazar-Alvarez, G. ^{[3
]}

Lopez-Ortega, A. ^{[4
,5
]}

Estrader, M. ^{[3
]}

Surinach, S. ^{[6
]}

Baro, M. D. ^{[6
]}

Sort, J. ^{[6
,7
]}

Nogues, J. ^{[4
,5
,7
]}

机构：

[1] NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA

[2] Paul Scherrer Inst, CH-5232 Villigen, Switzerland

[3] Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden

[4] CIN2 ICN CSIC, E-08193 Bellaterra, Barcelona, Spain

[5] Univ Autonoma Barcelona, Catalan Inst Nanotechnol ICN, E-08193 Bellaterra, Barcelona, Spain

[6] Univ Autonoma Barcelona, Dept Fis, E-08193 Bellaterra, Barcelona, Spain

[7] ICREA, Barcelona, Spain

来源：

JOURNAL OF APPLIED PHYSICS | 2013年 / 113卷 / 17期

关键词：

EXCHANGE BIAS; SHELL; CORE; BLOCKING;

D O I：

10.1063/1.4801423

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The magnetic responses of two nanoparticle systems comprised of Fe3O4/gamma-Mn2O3 (soft ferrimagnetic, FM/hard FM) and Fe3O4/MnO/gamma-Mn2O3 (soft FM/antiferromagnetic, AFM/hard FM) are compared, where the MnO serves to physically decouple the FM layers. Variation in the temperature and applied field allows for Small Angle Neutron Scattering (SANS) measurements of the magnetic moments both parallel and perpendicular to an applied field. Data for the bilayer particle indicate that the graded ferrimagnetic layers are coupled and respond to the field as a single unit. For the trilayer nanoparticles, magnetometry suggests a Curie temperature (T-C) approximate to 40 K for the outer gamma-Mn2O3 component, yet SANS reveals an increase in the magnetization associated with outer layer that is perpendicular to the applied field above T-C during magnetic reversal. This result suggests that the gamma-Mn2O3 magnetically reorients relative to the applied field as the temperature is increased above 40 K.

引用

页数：3

共 27 条

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