TY - JOUR

T1 - Active nematics with anisotropic friction

T2 - the decisive role of the flow aligning parameter

AU - Thijssen, Kristian

AU - Metselaar, Luuk

AU - Yeomans, Julia M.

AU - Doostmohammadi, Amin

PY - 2020/2/28

Y1 - 2020/2/28

N2 - We use continuum simulations to study the impact of anisotropic hydrodynamic friction on the emergent flows of active nematics. We show that, depending on whether the active particles align with or tumble in their collectively self-induced flows, anisotropic friction can result in markedly different patterns of motion. In a flow-aligning regime and at high anisotropic friction, the otherwise chaotic flows are streamlined into flow lanes with alternating directions, reproducing the experimental laning state that has been obtained by interfacing microtubule-motor protein mixtures with smectic liquid crystals. Within a flow-tumbling regime, however, we find that no such laning state is possible. Instead, the synergistic effects of friction anisotropy and flow tumbling can lead to the emergence of bound pairs of topological defects that align at an angle to the easy flow direction and navigate together throughout the domain. In addition to confirming the mechanism behind the laning states observed in experiments, our findings emphasise the role of the flow aligning parameter in the dynamics of active nematics.

AB - We use continuum simulations to study the impact of anisotropic hydrodynamic friction on the emergent flows of active nematics. We show that, depending on whether the active particles align with or tumble in their collectively self-induced flows, anisotropic friction can result in markedly different patterns of motion. In a flow-aligning regime and at high anisotropic friction, the otherwise chaotic flows are streamlined into flow lanes with alternating directions, reproducing the experimental laning state that has been obtained by interfacing microtubule-motor protein mixtures with smectic liquid crystals. Within a flow-tumbling regime, however, we find that no such laning state is possible. Instead, the synergistic effects of friction anisotropy and flow tumbling can lead to the emergence of bound pairs of topological defects that align at an angle to the easy flow direction and navigate together throughout the domain. In addition to confirming the mechanism behind the laning states observed in experiments, our findings emphasise the role of the flow aligning parameter in the dynamics of active nematics.

KW - TOPOLOGICAL DEFECTS

KW - DYNAMICS

KW - MOTION

U2 - 10.1039/c9sm01963d

DO - 10.1039/c9sm01963d

M3 - Journal article

C2 - 32003382

VL - 16

SP - 2065

EP - 2074

JO - Journal of Materials Chemistry

JF - Journal of Materials Chemistry

SN - 1744-683X

IS - 8

ER -