# Phase behavior of charged colloids at a fluid interface

Author Kelleher, Colm P · Guerra, Rodrigo E · Hollingsworth, Andrew D · Chaikin, Paul M 2017 See all Details

#### Abstract

We study the phase behavior of a system of charged colloidal particles that are electrostatically bound to an almost flat interface between two fluids. We show that, despite the fact that our experimental system consists of only $10^{3}$ - $10^{4}$ particles, the phase behavior is consistent with the theory of melting due to Kosterlitz, Thouless, Halperin, Nelson and Young (KTHNY). Using spatial and temporal correlations of the bond-orientational order parameter, we classify our samples into solid, isotropic fluid, and hexatic phases. We demonstrate that the topological defect structure we observe in each phase corresponds to the predictions of KTHNY theory. By measuring the dynamic Lindemann parameter, $\gamma_{L}(\tau)$, and the non-Gaussian parameter, $\alpha_{2}(\tau)$, of the displacements of the particles relative to their neighbors, we show that each of the phases displays distinctive dynamical behavior.

### Details

Title Phase behavior of charged colloids at a fluid interface Kelleher, Colm P · Guerra, Rodrigo E · Hollingsworth, Andrew D · Chaikin, Paul M 2017 Research Article eng 2017-01-30 00:00:00 Soft Condensed Matter · Condensed Matter
This is Version 1 of this record. We added this version on February 1, 2017. This version is based on an original data import from arXiv.org e-Print archive.