학술논문

Repulsive and attractive ferroglasses: a SAXS and XPCS study
Document Type
article
Source
Brazilian Journal of Physics. April 2009 39(1a)
Subject
75.50.Mn Magnetic liquids
61.10.i Xray diffraction and scattering
82.70.Dd Colloids
64.70.Pf Glass transitions
Language
English
ISSN
0103-9733
Abstract
A dynamical freezing, which is the analogous of a glass transition, is observed at large concentrations in aqueous dispersions of maghemite nanoparticles. We study experimentally the structure and the dynamical properties of two dense ferroglass-formers in two very distinct states of interparticle interaction, either strongly repulsive or attractive. The static structure of the magnetic colloidal dispersions is probed by means of Small Angle X-ray Scattering both in and without the presence of an external magnetic field. Translational dynamics of the repulsive glassformer are investigated by X ray Photon Correlation Spectroscopy. Slow dynamics and aging properties, which both become anisotropic under an applied field, are here investigated.