Emergent cometlike swarming of optically driven thermally active colloids
Physical Review Letters 112:6 (2014)
Abstract:
We propose a simple system of optically driven colloids that convert light into heat and move in response to self-generated and collectively generated thermal gradients. We show that the system exhibits self-organization into a moving cometlike swarm and characterize the structure and response of the swarm to a light-intensity-dependent external tuning parameter. We observe many interesting features in this nonequilibrium system including circulation and evaporation, intensity-dependent shape, density and temperature fluctuations, and ejection of hot colloids from the swarm tip. © 2014 American Physical Society.Self-assembly of catalytically active colloidal molecules: Tailoring activity through surface chemistry
Physical Review Letters 112:6 (2014)
Abstract:
A heterogeneous and dilute suspension of catalytically active colloids is studied as a nonequilibrium analogue of ionic systems, which has the remarkable feature of action-reaction symmetry breaking. Symmetrically coated colloids are found to join up to form self-assembled molecules that could be inert or have spontaneous activity in the form of net translational velocity and spin depending on their symmetry properties and their constituents. The type of activity can be adjusted by changing the surface chemistry and ambient variables that control the surface reactions and the phoretic drift. © 2014 American Physical Society.The arrival of the frequent: how bias in genotype-phenotype maps can steer populations to local optima
(2014)
Comment on "Elementary formula for the Hall conductivity of interacting systems"
(2014)