Phase separation, charge ordering, and pairing in layered three-dimensional systems - art. no. 113106

The processes of Coulomb gas ordering in a three-dimensional (3D) layered s ystem are studied by means of the Brownian dynamics approach. It is found t hat at different densities of the carriers, a 3D lattice of charges, as wel l as new specific structures, are possible in the system. At small densitie s, the particles inside the layers can associate into droplets that collect ively repel between neighboring layers, creating 3D ordering of the droplet s. These droplets possess local stripe structure that orders spontaneously along an arbitrary direction. The density of charge within the droplets is not a constant and changes with the average density. At higher densities, a specific ordering of the charges into the tetragonal-like or hexagonal-lik e structures is observed visually and described numerically. Specific "pair ing" of the charges from neighboring layers plays an essential role in the formation of all above structures.