Abstract
The magnetic properties of dispersions of magnetic silica microspheres have
been investigated by measuring the magnetization curves and the complex
magnetic susceptibility as a function of frequency and field amplitude. The
silica spheres appear to have a net permanent magnetic dipole moment, even
in zero field, which is increased significantly after a temporary exposure of
the silica colloids to a saturating magnetic field. The magnetic properties
of the microparticles in zero field are discussed in terms of the number and
the orientations of the embedded nanoparticle dipoles along an easy axis of
magnetization in the absence of an external field.
| Original language | Undefined/Unknown |
|---|---|
| Pages (from-to) | 46-54 |
| Number of pages | 16 |
| Journal | Journal of Physics: Condensed Matter |
| Volume | 19 |
| Publication status | Published - 2007 |