Ferromagnetism induced by strains in Pd nanoparticles

Y. Oba, Tetsuya Sato, T. Shinohara

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

The origin of the ferromagnetism that appears in the core region of Pd nanoparticles is discussed. According to many previous theoretical calculations, the onset of this ferromagnetism is closely related to the crystal structure and defects. In order to consider the contribution of crystal structure to the appearance of ferromagnetism in the Pd nanoparticles, we performed x-ray diffraction experiments and Warren-Averbach analysis. The results revealed that the standard deviation of strain Δε showed a positive correlation with the saturation magnetization, with the ferromagnetism appearing when Δε became larger than about 0.5%. This suggests that the strains induce internal ferromagnetism in the Pd nanoparticle. Compared to the critical magnitude of the strain at which ferromagnetism is predicted by the theoretical calculations, however, the estimated Δε is too small to explain the origin of ferromagnetism. Therefore, the strains smaller than the theoretical predictions should also give rise to the ferromagnetism or the strains should contribute to the magnetism not only through lattice expansion but also through changes in the crystal symmetry.

Original languageEnglish
Article number224417
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume78
Issue number22
DOIs
Publication statusPublished - 2008 Dec 1

Fingerprint

Ferromagnetism
ferromagnetism
Nanoparticles
nanoparticles
Crystal structure
crystal structure
Crystal defects
Crystal symmetry
Magnetism
Saturation magnetization
Crystal lattices
crystal defects
standard deviation
x ray diffraction
Diffraction
saturation
X rays
magnetization
expansion
symmetry

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this

Ferromagnetism induced by strains in Pd nanoparticles. / Oba, Y.; Sato, Tetsuya; Shinohara, T.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 78, No. 22, 224417, 01.12.2008.

Research output: Contribution to journalArticle

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