When driven out of equilibrium, particle systems can form complex spatial and dynamical patterns, even in the absence of attractive interactions. Non-equilibrium phase separation thus provides a promising alternative to control the structure and morphology of self-assembled materials. Using kinetic Monte Carlo simulations, we investigate the phase behavior of a binary system of particles of dissimilar size confined between semiflexible planar surfaces, where the diffusion energy barrier of each particle decreases with the fraction of larger particles in its local environment. The system autonomously reaches a cyclical non-equilibrium state characterized by the formation and dissipation of metastable micelle-like clusters with the small particles forming the core and the large ones the surrounding corona. The power spectrum of the fluctuations in the aggregation number exhibits 1/f noise, reminiscent of self-organized critical systems. We suggest that the dynamical metastability of the micellar structures arises from an inversion of the energy landscape, in which the relaxation dynamics of one of the species brings the other species out-of-equilibrium.

Dynamical inversion of the energy landscape promotes non-equilibrium self-organization of binary particle mixtures

255th National Meeting (2018)

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