https://doi.org/10.1140/epje/i2009-10490-x
Regular Article
Partial clustering prevents global crystallization in a binary 2D colloidal glass former
Fachbereich für Physik, Universität Konstanz, D-78457, Konstanz, Germany
* e-mail: peter.keim@uni-konstanz.de
Received:
27
April
2009
Revised:
9
June
2009
Accepted:
10
June
2009
Published online:
11
July
2009
A mixture of two types of super-paramagnetic colloidal particles with long-range dipolar interaction is confined by gravity to the flat interface of a hanging water droplet. The particles are observed by video microscopy and the dipolar interaction strength is controlled via an external magnetic field. The system is a model system to study the glass transition in 2D, and it exhibits partial clustering of the small particles (N. Hoffmann et al., Phys. Rev. Lett. 97, 078301 (2006)). This clustering is strongly dependent on the relative concentration 
of big and small particles. However, changing the interaction strength 
reveals that the clustering does not depend on the interaction strength. The partial clustering scenario is quantified using Minkowski functionals and partial structure factors. Evidence that partial clustering prevents global crystallization is discussed.
PACS: 82.70.Dd Colloids – / 64.70.P- Glass transitions of specific systems –
© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg, 2009
