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Title: Size- and Composition-Dependent Radio Frequency Magnetic Permeability of Iron Oxide Nanocrystals

Abstract

We investigate the size- and composition-dependent ac magnetic permeability of superparamagnetic iron oxide nanocrystals for radio frequency (RF) applications. The nanocrystals are obtained through high-temperature decomposition synthesis, and their stoichiometry is determined by Mossbauer spectroscopy. Two sets of oxides are studied: (a) as-synthesized magnetite-rich and (b) aged maghemite nanocrystals. All nanocrystalline samples are confirmed to be in the superparamagnetic state at room temperature by SQUID magnetometry. Through the one-turn inductor method, the ac magnetic properties of the nanocrystalline oxides are characterized. In magnetite-rich iron oxide nanocrystals, size-dependent magnetic permeability is not observed, while maghemite iron oxide nanocrystals show clear size dependence. The inductance, resistance, and quality factor of hand-wound inductors with a superparamagnetic composite core are measured. The superparamagnetic nanocrystals are successfully embedded into hand-wound inductors to function as inductor cores.

Authors:
; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE Advanced Research Projects Agency - Energy (ARPA-E)
OSTI Identifier:
1211208
DOE Contract Number:
DE-AR0000123
Resource Type:
Journal Article
Resource Relation:
Journal Name: ACS Nano; Journal Volume: 8; Journal Issue: 12
Country of Publication:
United States
Language:
English

Citation Formats

Yun, H, Liu, XY, Paik, T, Palanisamy, D, Kim, J, Vogel, WD, Viescas, AJ, Chen, J, Papaefthymiou, GC, Kikkawa, JM, Allen, MG, and Murray, CB. Size- and Composition-Dependent Radio Frequency Magnetic Permeability of Iron Oxide Nanocrystals. United States: N. p., 2014. Web. doi:10.1021/nn504711g.
Yun, H, Liu, XY, Paik, T, Palanisamy, D, Kim, J, Vogel, WD, Viescas, AJ, Chen, J, Papaefthymiou, GC, Kikkawa, JM, Allen, MG, & Murray, CB. Size- and Composition-Dependent Radio Frequency Magnetic Permeability of Iron Oxide Nanocrystals. United States. doi:10.1021/nn504711g.
Yun, H, Liu, XY, Paik, T, Palanisamy, D, Kim, J, Vogel, WD, Viescas, AJ, Chen, J, Papaefthymiou, GC, Kikkawa, JM, Allen, MG, and Murray, CB. 2014. "Size- and Composition-Dependent Radio Frequency Magnetic Permeability of Iron Oxide Nanocrystals". United States. doi:10.1021/nn504711g.
@article{osti_1211208,
title = {Size- and Composition-Dependent Radio Frequency Magnetic Permeability of Iron Oxide Nanocrystals},
author = {Yun, H and Liu, XY and Paik, T and Palanisamy, D and Kim, J and Vogel, WD and Viescas, AJ and Chen, J and Papaefthymiou, GC and Kikkawa, JM and Allen, MG and Murray, CB},
abstractNote = {We investigate the size- and composition-dependent ac magnetic permeability of superparamagnetic iron oxide nanocrystals for radio frequency (RF) applications. The nanocrystals are obtained through high-temperature decomposition synthesis, and their stoichiometry is determined by Mossbauer spectroscopy. Two sets of oxides are studied: (a) as-synthesized magnetite-rich and (b) aged maghemite nanocrystals. All nanocrystalline samples are confirmed to be in the superparamagnetic state at room temperature by SQUID magnetometry. Through the one-turn inductor method, the ac magnetic properties of the nanocrystalline oxides are characterized. In magnetite-rich iron oxide nanocrystals, size-dependent magnetic permeability is not observed, while maghemite iron oxide nanocrystals show clear size dependence. The inductance, resistance, and quality factor of hand-wound inductors with a superparamagnetic composite core are measured. The superparamagnetic nanocrystals are successfully embedded into hand-wound inductors to function as inductor cores.},
doi = {10.1021/nn504711g},
journal = {ACS Nano},
number = 12,
volume = 8,
place = {United States},
year = 2014,
month =
}
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