Formation and propagation of solitonlike defect clusters in confined active nematics with chiral anchoring

Abstract

Understanding the emergent nonequilibrium dynamics of collective units is crucial for steering and engineering active many-body systems. Here, we explore flow transitions and topological defect dynamics of channel-confined active nematics under chiral boundary anchoring. We discover that the anchoring chirality can engender unanticipated solitonlike defect clusters, where activity-excited topological defects self-localize into small cohesive clusters that unidirectionally propagate as dynamically stable solitons. Defects continuously move, nucleate, and annihilate locally, which causes periodic cluster reconfiguration and energy oscillations, reflecting the structural degeneracy of defect clusters. The boundary anchoring chirality not only determines the direction of background active flows but also remarkably speeds them up, which underlies the emergence of solitonlike defect clusters. We further show that the periodicity and structural reconfiguration of defect clusters can be tuned using specified initial orientation fields. These findings could motivate direct programmatic control strategies for engineered active materials and provide insights into the collective behaviors of living organisms within confining tracks during life processes.