Superparamagnetic behavior of Fe-doped SnO{sub 2} nanoparticles

Journal Article · Thu Feb 20 00:00:00 EST 2014 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4866611· OSTI ID:22266050

Hachisu, M.; Onuma, K.; Kondo, T.; Miike, K.; Miyasaka, T.; Mori, K.; Ichiyanagi, Y. ^[1]

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1. Department of Physics, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama, Kanagawa 240-8501 (Japan)

SnO{sub 2} is an n-type semiconductor with a wide band gap of 3.62 eV, and SnO{sub 2} nanoparticles doped with magnetic ions are expected to realized new diluted magnetic semiconductors (DMSs). Realizing ferromagnetism at room temperature is important for spintronics device applications, and it is interesting that the magnetic properties of these DMS systems can be varied significantly by modifying the preparation methods or conditions. In this study, the magnetic properties of Fe-doped (3% and 5%) SnO{sub 2} nanoparticles, prepared using our novel chemical preparation method and encapsulated in amorphous SiO{sub 2}, were investigated. The particle size (1.8–16.9 nm) and crystal phase were controlled by the annealing temperature. X-ray diffraction confirmed a rutile SnO{sub 2} single-phase structure for samples annealed at 1073–1373 K, and the composition was confirmed using X-ray fluorescence analysis. SQUID magnetometer measurements revealed superparamagnetic behavior of the 5%-Fe-doped sample at room temperature, although SnO{sub 2} is known to be diamagnetic. Magnetization curves at 5 K indicated that the 3%-Fe-doped has a larger magnetization than that of the 5%-Fe-doped sample. We conclude that the magnetization of the 5%-Fe-doped sample decreased at 5 K due to the superexchange interaction between the antiferromagnetic coupling in the nanoparticle system.

• OSTI ID: 22266050
• Journal Information: AIP Conference Proceedings, Vol. 1585, Issue 1; Conference: IRAGO conference 2013, Aichi (Japan), 24-25 Oct 2013; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
77 NANOSCIENCE AND NANOTECHNOLOGY
ANNEALING
ANTIFERROMAGNETISM
CHEMICAL PREPARATION
DOPED MATERIALS
MAGNETIC PROPERTIES
MAGNETIC SEMICONDUCTORS
MAGNETIZATION
NANOSTRUCTURES
PARTICLE SIZE
PARTICLES
RUTILE
SILICA
SILICON OXIDES
SQUID DEVICES
SUPERPARAMAGNETISM
TIN OXIDES
X-RAY DIFFRACTION
X-RAY FLUORESCENCE ANALYSIS