Magnetocaloric effect in bulk and nanostructured Gd3Fe5O12 materials

被引：75

作者：

Phan, M. H. ^{[1
]}

Morales, M. B. ^{[1
]}

Chinnasamy, C. N. ^{[2
,3
]}

Latha, B. ^{[2
,3
]}

Harris, V. G. ^{[2
,3
]}

Srikanth, H. ^{[1
]}

机构：

[1] Univ S Florida, Dept Phys, Tampa, FL 33620 USA

[2] Northeastern Univ, CM3IC, Boston, MA 02115 USA

[3] Northeastern Univ, Dept Elect & Comp Engn, Boston, MA 02115 USA

来源：

JOURNAL OF PHYSICS D-APPLIED PHYSICS | 2009年 / 42卷 / 11期

基金：

美国国家科学基金会;

关键词：

MAGNETIC-PROPERTIES;

D O I：

10.1088/0022-3727/42/11/115007

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We report here the magnetocaloric effect (MCE) in bulk and nanostructured gadolinium iron garnets (Gd3Fe5O12). When compared with the bulk counterpart, the magnitude of the MCE is smaller for nanostructured samples with an average grain size of 50 nm, but increases when the grain size decreases to 35 nm. For the bulk sample, the MCE curves show a broad peak at 35 K; this peak is found to shift to lower temperatures for the nanostructured samples. The origin of the MCE peak for the bulk sample is associated with the intrinsic magnetic frustration and the ferromagnetic ordering of the Gd sublattice below 90K, while for nanostructured garnets it is additionally ascribed to the surface spin disorder and particle blocking effects. While blocking is detrimental to achieving large MCE, surface spin disorder is found to enhance it under high applied fields.

引用

页数：7

共 33 条

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