Low-Density Ordered Phase in Brownian Dipolar Colloidal Suspensions

Agarwal, Amit K. and Yethiraj, Anand (2009) Low-Density Ordered Phase in Brownian Dipolar Colloidal Suspensions. Physical Review Letters, 102. ISSN 1079-7114

[English] PDF - Published Version Available under License Creative Commons Attribution Non-commercial. Download (831kB)

Abstract

We study the low volume fraction and electric field phase behavior of a Brownian colloidal suspension. On the application of a uniform ac field, we find a novel phase where chains of particles aggregate to form a well defined cellular network, consisting of particle-free ‘‘voids’’ surrounded by a percolating network of particle-rich walls. This cellular structure is stable to very long times, indicative of an equilibrium thermodynamic phase. The cell-cell spacing is not sensitive to the concentration of the sample but scales with sample thickness. Any self-consistent mechanism for the existence of this void phase must consist of long-ranged repulsions and shorter-ranged attractions.

Actions (login required)

View Item