Magnetic properties of iron-oxide small particles prepared on aluminum and MgO(100)

K. Fukumura, A. Nakanishi, Tatsuo Fujii, T. Kobayashi

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Magnetic properties of small particles of iron oxide on an aluminum foil and a single crystal of MgO are studied by conversion electron Mössbauer spectroscopy (CEMS) at low temperature. The average thickness of the oxide layers is 3.0 nm on aluminum and 1.2 nm on MgO. The CEMS spectra are observed at 15-300 K with a gas-filled proportional counter which was developed in our laboratory. The hyperfine fields in the surface layer and in the core of the particles are separated. The diameter and magnetic anisotropy energy constant are 3.7 nm and 0.87 × 105 J/m3, and 3.5 nm and 2.4 × 105 J/m3, respectively, for small particles on aluminum and MgO. The large difference in the anisotropy constants of small particles on aluminum and MgO is attributed to the enhanced surface anisotropy, which may be caused by diffusion of magnesium ions into the lattice of iron oxide. The superparamagnetic blocking temperatures of these particles are 71 and 94 K, respectively.

Original languageEnglish
Pages (from-to)175-180
Number of pages6
JournalJournal of Magnetism and Magnetic Materials
Volume145
Issue number1-2
DOIs
Publication statusPublished - Mar 1 1995

Fingerprint

Aluminum
Iron oxides
iron oxides
Magnetic properties
Electron spectroscopy
magnetic properties
aluminum
Anisotropy
Proportional counters
Aluminum foil
Magnetic anisotropy
anisotropy
electron spectroscopy
Oxides
Magnesium
Gases
Single crystals
Ions
proportional counters
Temperature

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Magnetic properties of iron-oxide small particles prepared on aluminum and MgO(100). / Fukumura, K.; Nakanishi, A.; Fujii, Tatsuo; Kobayashi, T.

In: Journal of Magnetism and Magnetic Materials, Vol. 145, No. 1-2, 01.03.1995, p. 175-180.

Research output: Contribution to journalArticle

@article{5a4338445c9f403db8c6d7cb4e4f4d55,
title = "Magnetic properties of iron-oxide small particles prepared on aluminum and MgO(100)",
abstract = "Magnetic properties of small particles of iron oxide on an aluminum foil and a single crystal of MgO are studied by conversion electron M{\"o}ssbauer spectroscopy (CEMS) at low temperature. The average thickness of the oxide layers is 3.0 nm on aluminum and 1.2 nm on MgO. The CEMS spectra are observed at 15-300 K with a gas-filled proportional counter which was developed in our laboratory. The hyperfine fields in the surface layer and in the core of the particles are separated. The diameter and magnetic anisotropy energy constant are 3.7 nm and 0.87 × 105 J/m3, and 3.5 nm and 2.4 × 105 J/m3, respectively, for small particles on aluminum and MgO. The large difference in the anisotropy constants of small particles on aluminum and MgO is attributed to the enhanced surface anisotropy, which may be caused by diffusion of magnesium ions into the lattice of iron oxide. The superparamagnetic blocking temperatures of these particles are 71 and 94 K, respectively.",
author = "K. Fukumura and A. Nakanishi and Tatsuo Fujii and T. Kobayashi",
year = "1995",
month = "3",
day = "1",
doi = "10.1016/0304-8853(94)00864-7",
language = "English",
volume = "145",
pages = "175--180",
journal = "Journal of Magnetism and Magnetic Materials",
issn = "0304-8853",
publisher = "Elsevier",
number = "1-2",

}

TY - JOUR

T1 - Magnetic properties of iron-oxide small particles prepared on aluminum and MgO(100)

AU - Fukumura, K.

AU - Nakanishi, A.

AU - Fujii, Tatsuo

AU - Kobayashi, T.

PY - 1995/3/1

Y1 - 1995/3/1

N2 - Magnetic properties of small particles of iron oxide on an aluminum foil and a single crystal of MgO are studied by conversion electron Mössbauer spectroscopy (CEMS) at low temperature. The average thickness of the oxide layers is 3.0 nm on aluminum and 1.2 nm on MgO. The CEMS spectra are observed at 15-300 K with a gas-filled proportional counter which was developed in our laboratory. The hyperfine fields in the surface layer and in the core of the particles are separated. The diameter and magnetic anisotropy energy constant are 3.7 nm and 0.87 × 105 J/m3, and 3.5 nm and 2.4 × 105 J/m3, respectively, for small particles on aluminum and MgO. The large difference in the anisotropy constants of small particles on aluminum and MgO is attributed to the enhanced surface anisotropy, which may be caused by diffusion of magnesium ions into the lattice of iron oxide. The superparamagnetic blocking temperatures of these particles are 71 and 94 K, respectively.

AB - Magnetic properties of small particles of iron oxide on an aluminum foil and a single crystal of MgO are studied by conversion electron Mössbauer spectroscopy (CEMS) at low temperature. The average thickness of the oxide layers is 3.0 nm on aluminum and 1.2 nm on MgO. The CEMS spectra are observed at 15-300 K with a gas-filled proportional counter which was developed in our laboratory. The hyperfine fields in the surface layer and in the core of the particles are separated. The diameter and magnetic anisotropy energy constant are 3.7 nm and 0.87 × 105 J/m3, and 3.5 nm and 2.4 × 105 J/m3, respectively, for small particles on aluminum and MgO. The large difference in the anisotropy constants of small particles on aluminum and MgO is attributed to the enhanced surface anisotropy, which may be caused by diffusion of magnesium ions into the lattice of iron oxide. The superparamagnetic blocking temperatures of these particles are 71 and 94 K, respectively.

UR - http://www.scopus.com/inward/record.url?scp=0029271474&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029271474&partnerID=8YFLogxK

U2 - 10.1016/0304-8853(94)00864-7

DO - 10.1016/0304-8853(94)00864-7

M3 - Article

AN - SCOPUS:0029271474

VL - 145

SP - 175

EP - 180

JO - Journal of Magnetism and Magnetic Materials

JF - Journal of Magnetism and Magnetic Materials

SN - 0304-8853

IS - 1-2

ER -