1.
Phys Rev Lett
; 104(12): 127205, 2010 Mar 26.
Artigo
em Inglês
| MEDLINE
| ID: mdl-20366563
RESUMO
We report magnetic measurements on a macroscopic three-dimensional fcc array of iron-oxide nanoparticles. We observe typical nanomagnetism for the randomly packed configuration of nanoparticles, including dynamical freezing and superparamagnetism. By contrast, the nanoparticle "atoms" in the fcc configuration that form the crystal exhibit a low coercivity that is weakly temperature dependent with no superparamagnetism up to 400 K.