کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1801083 | 1024558 | 2009 | 7 صفحه PDF | دانلود رایگان |
We investigate the effect of external magnetic fields on the magnetic structure of thin films from magnetic nanoparticles (MNP) with dipolar interaction. Such fields are present, for example, if samples are scanned with magnetic probes. Numerical simulations and experimental magnetic force microscopy (MFM) studies are presented. Numerically, we have calculated the magnetization pattern of single-layer and multilayer MNP thin films. The calculations show that unperturbed single-layer MNP films have an in-plane orientation of the magnetization with a flux-closure-domain pattern. An external field generated by a point dipole above the film induces locally an out-of-plane configuration of the magnetization. In the corresponding MFM images, the domain pattern in the film is erased and a stripe-like contrast enhancement at the edges appears. Multilayer films are found to be more robust against external fields than monolayers.
Journal: Journal of Magnetism and Magnetic Materials - Volume 321, Issue 22, November 2009, Pages 3719–3725