Magnetism

Magnetic nanoparticles may self-assemble into larger structures which have properties that differ significantly from those of both individual particles and their bulk counterparts. Such nanoparticle-materials are of potential interest for use in e.g., new types of permanent magnets and magnetic sensors.

Our research focuses on understanding (a) the magnetic properties of individual nanoparticles and (b) the properties of assemblies of nanoparticles. We study in detail the influence of inter-particle interactions by quantifying and controlling the interplay between nanoparticle arrangement and magnetic order.

Nano-scale magnet

 Image from M. Varón, M. Beleggia, T. Kasama, R.J. Harrison, R.E. Dunin-Borkowski, V.F. Puntes and C. Frandsen, Scientific Reports 3 (2013) 1234.

Selected recent publications on magnetic nanoparticles

M. Varon, M. Beleggia, T. Kasama, R.J. Harrison, R.E. Dunin-Borkowski, V.F. Puntes, C. Frandsen, Dipolar magnetism in ordered and disordered low-dimensional nanoparticle assemblies, Scientific Reports 3 (2013) 1234.

C. Frandsen, K. Lefmann, B. Lebech, C.R.H. Bahl, E. Brok, S.N. Ancoña, L. Theil Kuhn, L. Keller, T. Kasama, L.C. Gontard, and S. Mørup, Spin reorientation in a-Fe2O3 nanoparticles induced by inter-particle exchange interactions in a-Fe2O3/NiO nanocomposites, Physical Review B 84 (2011) 214435.

S. Mørup, M.F. Hansen and C. Frandsen, Magnetic interactions between nanoparticles, Beilstein Journal of Nanotechnology 1 (2010) 182-190.

C. Frandsen, B. Burton, H.K. Rasmussen, S.A. McEnroe, and S. Mørup, Magnetic clusters in hematite-ilmenite solid solutions, Physical Review B 81 (2010) 224423.

H. Jacobsen, K. Lefmann, E. Brok, C. Frandsen, and S. Mørup, Temperature dependence of the magnetization of canted spin structures, Journal of Magnetism and Magnetic Materials 324 (2012) 3218.

S. Mørup, E. Brok, and C. Frandsen, Spin Structures in Magnetic Nanoparticles, Journal of Nanomaterials 2013 (2013) 720629.

Facilities - Magnetism

  • Mössbauer spectroscopy laboratory

Kontakt

Cathrine Frandsen
Professor, Sektionsleder
DTU Fysik