Dr. Andrés Arango Restrepo: Non-equilibrium thermodynamics of active matter self-organization

Understanding how dissipative processes drive the emergence of order is fundamental to the study of out-of-equilibrium systems. In this work, we explore two paradigmatic cases of nonequilibrium self-organization: the formation of dissipative self-assembled structures and the collective behavior of catalytic Janus particles, both, in active matter systems. Starting from a non-equilibrium thermodynamic framework, we establish a predictive criterion for the emergence of self-assembled morphologies based on entropy production and energy dissipation. Our analysis reveals that such structures emerge near nonequilibrium energy-free optimal states, where the interplay between chemical gradients, transport, and structural dynamics governs the evolution of the system. Complementing this theoretical perspective, we investigate active colloidal systems composed of catalytic Janus particles, characterizing their behavior by entropy production. We demonstrate how their collective dynamics and emergent organization are controlled by local dissipation mechanisms, and where we define the non-equilibrium chemical potential of the active particles. Taken together, these studies unify the description of the self-organization of active matter, providing a thermodynamic basis for the design and control of functional materials under non-equilibrium conditions.

Kindly invited!