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

TL;DR

This study experimentally observes various condensed phases of quasi-planar core-softened colloids in two dimensions, confirming many theoretical predictions through experiments and simulations.

Contribution

It provides the first experimental realization and characterization of multiple predicted condensed phases of core-softened colloids in two dimensions.

Findings

Observation of hexagonal, square, chain-like, and honeycomb phases

Agreement between experimental results and Monte Carlo simulations

Identification of phase behavior across a broad density range

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.