Orbital and spin moments of 5 to 11 nm Fe{sub 3}O{sub 4} nanoparticles measured via x-ray magnetic circular dichroism

Journal Article · Wed May 07 00:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4869277· OSTI ID:22273502

Cai, Y. P.; Trevino, M.; Westover, A.; Turley, S. ^[1]; Harrison, R. G.; Hancock, J. M. ^[2]; Scherz, A.; Reid, A.; Wu, B.; Graves, C.; Wang, T.; Liu, T.; Dürr, H. ^[3]

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1. Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602 (United States)
2. Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602 (United States)
3. SLAC National Accelerator Laboratory, Stanford Institute for Materials and Energy Science (SIMES), Menlo Park, California 94025 (United States)

The orbital and spin contributions to the magnetic moment of Fe in Fe{sub 3}O{sub 4} nanoparticles were measured using X-ray magnetic circular dichroism (XMCD). Nanoparticles of different sizes, ranging from 5 to 11 nm, were fabricated via organic methods and their magnetic behavior was characterized by vibrating sample magnetometry (VSM). An XMCD signal was measured for three different samples at 300 K and 80 K. The extracted values for the orbital and spin contributions to the magnetic moment showed a quenching of the orbital moment and a large spin moment. The calculated spin moments appear somewhat reduced compared to the value expected for bulk Fe{sub 3}O{sub 4}. The spin moments measured at 80 K are larger than at 300 K for all the samples, revealing significant thermal fluctuations effects in the nanoparticle assemblies. The measured spin moment is reduced for the smallest nanoparticles, suggesting that the magnetic properties of Fe{sub 3}O{sub 4} nanoparticles could be altered when their size reaches a few nanometers.

• OSTI ID: 22273502
• Journal Information: Journal of Applied Physics, Vol. 115, Issue 17; Conference: 55. annual conference on magnetism and magnetic materials, Atlanta, GA (United States), 14-18 Nov 2010; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
77 NANOSCIENCE AND NANOTECHNOLOGY
COMPARATIVE EVALUATIONS
FLUCTUATIONS
IRON OXIDES
MAGNETIC CIRCULAR DICHROISM
MAGNETIC MOMENTS
MAGNETIC PROPERTIES
NANOSTRUCTURES
PARTICLES
QUENCHING
SPIN
TEMPERATURE DEPENDENCE
VIBRATING SAMPLE MAGNETOMETERS
X RADIATION