It is well known that periodic potentials can be used to induce freezing and melting in colloids. Here, we transfer this concept to active systems and find the emergence of a so-far unknown active matter phase in between the frozen solid-like phase and the molten phase. This phase of "active adaptolates" adopts the geometry of the underlying lattice like the frozen phase, maintains ballistic dynamics like the molten phase, and percolates. In particular, this finding creates a route to use external fields for designing the intrinsic structure of active systems without qualitatively affecting their dynamics.
@article{arxiv.2305.08438,
title = {Active adaptolates: motility-induced percolating structures with an adaptive packing geometry},
author = {Aritra K. Mukhopadhyay and Peter Schmelcher and Benno Liebchen},
journal= {arXiv preprint arXiv:2305.08438},
year = {2026}
}