Transport dynamics of colloidal behaviour in active nematic phase

We investigate the dynamics of colloidal particles in active nematic fluids, contrasting their behavior with passive nematic phases. Unlike passive systems, active nematics continuously consume energy at the microscale, leading to spontaneous flows, defect proliferation, and fundamentally altered free energy landscapes. This drives the system far from equilibrium, producing transport behaviors that are highly non-intuitive and absent in passive nematics. While colloidal dynamics in passive nematic environments such as anisotropic diffusion and defect-mediated migration are well documented, their behavior in active nematics remains largely unexplored. Using a hybrid lattice Boltzmann framework integrated with active nematic hydrodynamics, we systematically study how activity strength, colloidal size, and boundary conditions affect particle trajectories and force distributions. We connect mean squared displacement profiles to continuous time random walk theories, revealing long-time anomalous diffusion driven by active flows rather than thermal fluctuations. Detailed force analysis uncovers unique hydrodynamic and non-hydrodynamic contributions arising from activity, leading to distinctly non-Stokesian dynamics. These insights advance our understanding of colloidal transport and organization in active materials, with implications for designing responsive soft matter systems.