2021/02/04 by Siyuan Yang, Mingji Huang, Yongfeng Zhao +2
Engineering · Physics and Astronomy · #Active matter #Biology #Brownian motion #Classical mechanics #Euglena gracilis #Geometry #Light field #Micro and Nano Robotics #Microfluidic and Bio-sensing Technologies #Microscale chemistry #Molecular Communication and Nanonetworks #Optics #Perpendicular #Physics #Polarization (electrochemistry) #Quantum mechanics #cond-mat.soft #cond-mat.stat-mech #physics.bio-ph
paper · pdf · doi:10.1103/physrevlett.126.058001
published as Phys. Rev. Lett. 126, 058001 (2021) · 5 figures, published in PRL
openalex publication_date 2021/02/04 · arxiv created 2021/02/06 · arxiv updated 2021/02/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate how light polarization affects the motion of photoresponsive algae, Euglena gracilis. In a uniformly polarized field, cells swim approximately perpendicular to the polarization direction and form a nematic state with zero mean velocity. When light polarization varies spatially, cell motion is modulated by local polarization. In such light fields, cells exhibit complex spatial distribution and motion patterns which are controlled by topological properties of the underlying fields; we further show that ordered cell swimming can generate directed transporting fluid flow. Experimental results are quantitatively reproduced by an active Brownian particle model in which particle motion direction is nematically coupled to local light polarization.