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Title: Origin of reduced magnetization and domain formation in small magnetite nanoparticles

Abstract

We compare the structural, chemical, and magnetic properties of magnetite nanoparticles. Aberration corrected scanning transmission electron microscopy reveals the prevalence of antiphase boundaries in nanoparticles that have significantly reduced magnetization, relative to the bulk. We show that atomistic magnetic modelling of nanoparticles with and without these defects reveal the origin of the reduced moment. Strong antiferromagnetic interactions across antiphase boundaries support multiple magnetic domains even in particles as small as 12–14 nm.

Authors:
 [1];  [2];  [1];  [3];  [4];  [4];  [5];  [2];  [1];  [4];  [1]
  1. Univ. of York (United Kingdom). Dept. of Physics
  2. SuperSTEM, Daresbury (United Kingdom)
  3. Carnegie Mellon Univ., Pittsburgh, PA (United States). Physics Dept.; Univ. of Electronic Science and Technology of China, Chengdu (China). State Key Laboratory of Electronic Thin Films and Integrated Devices
  4. Carnegie Mellon Univ., Pittsburgh, PA (United States). Physics Dept.
  5. Univ. of Cadiz, Puerto Real (Spain). Dept. of Computer Science and Engineering
Publication Date:
Research Org.:
Carnegie Mellon Univ., Pittsburgh, PA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1366451
Grant/Contract Number:
FG02-08ER46481
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; magnetic properties and materials; nanoscale materials

Citation Formats

Nedelkoski, Zlatko, Kepaptsoglou, Demie, Lari, Leonardo, Wen, Tianlong, Booth, Ryan A., Oberdick, Samuel D., Galindo, Pedro L., Ramasse, Quentin M., Evans, Richard F. L., Majetich, Sara, and Lazarov, Vlado K. Origin of reduced magnetization and domain formation in small magnetite nanoparticles. United States: N. p., 2017. Web. doi:10.1038/srep45997.
Nedelkoski, Zlatko, Kepaptsoglou, Demie, Lari, Leonardo, Wen, Tianlong, Booth, Ryan A., Oberdick, Samuel D., Galindo, Pedro L., Ramasse, Quentin M., Evans, Richard F. L., Majetich, Sara, & Lazarov, Vlado K. Origin of reduced magnetization and domain formation in small magnetite nanoparticles. United States. doi:10.1038/srep45997.
Nedelkoski, Zlatko, Kepaptsoglou, Demie, Lari, Leonardo, Wen, Tianlong, Booth, Ryan A., Oberdick, Samuel D., Galindo, Pedro L., Ramasse, Quentin M., Evans, Richard F. L., Majetich, Sara, and Lazarov, Vlado K. Mon . "Origin of reduced magnetization and domain formation in small magnetite nanoparticles". United States. doi:10.1038/srep45997. https://www.osti.gov/servlets/purl/1366451.
@article{osti_1366451,
title = {Origin of reduced magnetization and domain formation in small magnetite nanoparticles},
author = {Nedelkoski, Zlatko and Kepaptsoglou, Demie and Lari, Leonardo and Wen, Tianlong and Booth, Ryan A. and Oberdick, Samuel D. and Galindo, Pedro L. and Ramasse, Quentin M. and Evans, Richard F. L. and Majetich, Sara and Lazarov, Vlado K.},
abstractNote = {We compare the structural, chemical, and magnetic properties of magnetite nanoparticles. Aberration corrected scanning transmission electron microscopy reveals the prevalence of antiphase boundaries in nanoparticles that have significantly reduced magnetization, relative to the bulk. We show that atomistic magnetic modelling of nanoparticles with and without these defects reveal the origin of the reduced moment. Strong antiferromagnetic interactions across antiphase boundaries support multiple magnetic domains even in particles as small as 12–14 nm.},
doi = {10.1038/srep45997},
journal = {Scientific Reports},
number = ,
volume = 7,
place = {United States},
year = {Mon Apr 10 00:00:00 EDT 2017},
month = {Mon Apr 10 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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Citation Metrics:
Cited by: 1work
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