Please use this identifier to cite or link to this item:
|Type:||Artigo de periódico|
|Title:||Magnetic Moment Of Fe3 O4 Films With Thicknesses Near The Unit-cell Size|
De Siervo A.
|Abstract:||We perform a systematic study on the evolution of the magnetic spin moment (ms) of epitaxial - and -magnetite films of increasing thickness. The ultrathin films are characterized by low-energy electron diffraction, x-ray absorption spectroscopy, and x-ray magnetic circular dichroism (XMCD). By employing sum rules on the XMCD spectra we obtain ms=3.6 μB/f.u. for samples of around 35 Å. This is considered a bulk value and has been reported only for films more than 10 times thicker. Moreover, we show that even 10-Å-thick magnetite already presents a significant magnetic moment. For both grown directions the moment increases similarly with the thickness. The ferromagnetic behavior for each iron ion site (Feocta2+, Feocta3+, Fetetra3+) of Fe3O4 is measured by monitoring XMCD peaks. The deduced hysteresis curves (per ion, per site) exhibit a coercive field of 300 Oe. Our results show that both the ferrimagnetic order and the bulk moment value are preserved at room temperature around the thickness of 2 unit cells.|
|Editor:||American Physical Society|
|Appears in Collections:||Unicamp - Artigos e Outros Documentos|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.