摘要： The active diffusion and sedimentation equilibrium of rod-like nanoswimmers with length L are investigated by dissipative particle dynamics. In the absence of propulsion, the nanorod has the rotational correlation time τ and mobility μ 0 , which vary with L . On the basis of the mean squared displacement, the diffusive behavior of rod-like nanoswimmers subject to active force F a is found to follow ( D − D 0 ) ∝ ( μ 0 F a ) 2 τ , where D 0 depicts the Brownian diffusivity. When the nanoswimmer suspension is under the external force F e , the balance between the downward migration and upward active diffusion yields the sedimentation length δ = D /( μ 0 F e ), which no longer obeys δ 0 = k B T / F e obtained from the Einstein-Smoluchowski relationship, D 0 = μ 0 k B T . Different from the suspension of passive rods, the polar order is clearly seen for active rods. The local polar order is essentially constant within the distance of about 2 δ from the bottom wall but decays as the distance is further increased. In this work, the active Peclet number is small compared to unity and the maximum polar order grows linearly with F e / F a . The polar order arises because it is easier for the nanoswimmer with the swimming direction opposite to the external force to escape from the bottom wall. The active diffusion and sedimentation equilibrium of rod-like nanoswimmers with length L are investigated by dissipative particle dynamics. 其他題名： Soft Matter 出版者： England 出版日期： 2015-03-28 出處： Soft matter, 2015-03, Vol.11 (12), p.2416-2422 識別號： ISSN: 1744-683X 識別號： ISSN: 1744-6848 識別號： EISSN: 1744-6848 識別號： DOI: 10.1039/c4sm02701a 識別號： PMID: 25662710
