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arXiv · 0707.3767

Observation of condensed phases of quasi-planar core-softened colloids

N. Osterman·D. Babič·I. Poberaj·J. Dobnikar·P. Ziherl
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Abstract

We experimentally study the condensed phases of repelling core-softened spheres in two dimensions. The dipolar pair repulsion between superparamagnetic spheres trapped in a thin cell is induced by a transverse magnetic field and softened by suitably adjusting the cell thickness. We scan a broad density range and we materialize a large part of the theoretically predicted phases in systems of core-softened particles, including expanded and close-packed hexagonal, square, chain-like, stripe/labyrinthine, and honeycomb phase. Further insight into their structure is provided by Monte Carlo simulations.

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N. Osterman, D. Babič, I. Poberaj, J. Dobnikar, P. Ziherl. 2007-07-25. Observation of condensed phases of quasi-planar core-softened colloids. https://doi.org/10.1103/physrevlett.99.248301

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