| Zugriffsnummer | 42148 |
| Dokumenttyp | Zeitschriftenartikel |
| Peer Review | mit Peer Review |
| Sprache | Englisch |
| Titel | Dipolar-coupled moment correlations in clusters of magnetic nanoparticles |
| Autor(in); Institution |
Bender, P.; Departamento CITIMAC, Faculty of Science, University of Cantabria, Santander, SPAIN
Wetterskog, E.; Department of Engineering Sciences, Uppsala University, Uppsala, SWEDEN
Honecker, D.; Institut Laue-Langevin, Grenoble, FRANCE
Fock, J.; Technical University of Denmark, Kongens Lyngby, DENMARK
Frandsen, C.; Technical University of Denmark, Kongens Lyngby, DENMARK
Moerland, C.; Department of Applied Physics, Technische Universiteit Eindhoven, Eindhoven, THE NETHERLANDS
Bogart, L.K:; UCL Healthcare Biomagnetics Laboratory, University College London, London, UNITED KINGDOM
Posth, Oliver; 8.2, Biosignale, PTB-Berlin
Szczerba, W.; Bundesanstalt für Materialforschung und-Prüfung, Berlin, GERMANY; AGH University of Science and Technology, Krakow, POLAND
Gavilán, H.; Instituto de Ciencia de Materiales de Madrid, ICMM/CSIC, Madrid, SPAIN
Costo, R.; Instituto de Ciencia de Materiales de Madrid, ICMM/CSIC, Madrid, SPAIN
Fernández-Díaz, M.T.; Institut Laue-Langevin, Grenoble, FRANCE
González-Alonso, D.; Departamento CITIMAC, Faculty of Science, University of Cantabria, Santander, SPAIN
Fernández Barquín, L.; Departamento CITIMAC, Faculty of Science, University of Cantabria, Santander, SPAIN
Johansson, C.; RISE Acreo, Göteborg, SWEDEN
|
| Quelle/Jahr | Physical Review B: 98 (2018), 1 - 11 |
| Artikelnummer | 224420 |
| ISSN | 2469-9950 (PRINT) ; 2469-9969 (ONLINE) |
| DOI | |
| Verlag | Woodbury, NY: American Physical Society |
| Zusammenfassung | Here, we resolve the nature of the moment coupling between 10-nm dimercaptosuccinic acid–coated magnetic nanoparticles. The individual iron oxide cores were composed of <95% maghemite and agglomerated to clusters. At room temperature the ensemble behaved as a superparamagnet according to Mössbauer and magnetization measurements, however, with clear signs of dipolar interactions. Analysis of temperature-dependent ac susceptibility data in the superparamagnetic regime indicates a tendency for dipolar-coupled anticorrelations of the core moments within the clusters. To resolve the directional correlations between the particle moments we performed polarized small-angle neutron scattering and determined the magnetic spin-flip cross section of the powder in low magnetic field at 300 K. We extract the underlying magnetic correlation function of the magnetization vector field by an indirect Fourier transform of the cross section. The correlation function suggests nonstochastic preferential alignment between neighboring moments despite thermal fluctuations, with anticorrelations clearly dominating for next-nearest moments. These tendencies are confirmed by Monte Carlo simulations of such core clusters. |
| Themenbereich der Metrologie | Metrologie in der Medizin |
| Forschungsprojekt | Grant Agreement No. 604448 (NanoMag). |
Zitierung
Bender, P., Wetterskog, E., Honecker, D., Fock, J., Frandsen, C., Moerland, C., Bogart, L., Posth, O., Szczerba, W., Gavilán, H., Costo, R., Fernández-Díaz, M., González-Alonso, D., Fernández Barquín, L., & Johansson, C. (2018). Dipolar-coupled moment correlations in clusters of magnetic nanoparticles. Physical Review B, 98, 1–11. https://doi.org/10.1103/physrevb.98.224420