Anisotropy of average potential energy of passive plate in bacterial suspensions  

作　　者：Luhui Ning Ziwei Xiao Yuxin Tian Hongwei Zhu Yi Peng Peng Liu Ning Zheng Mingcheng Yang Junqing Chen 宁鲁慧;肖紫薇;田宇鑫;朱红伟;彭毅;刘鹏;郑宁;杨明成;陈君青

机构地区：[1]Beijing Key Laboratory of Optical Detection Technology for Oil and Gas,China University of Petroleum-Beijing,Beijing 102249,China [2]Basic Research Center for Energy Interdisciplinary,College of Science,China University of Petroleum-Beijing,Beijing 102249,China [3]School of Physics,Beijing Institute of Technology,Beijing 100081,China [4]School of Physical Science and Technology,Key Laboratory of Magnetism and Magnetic Materials for Higher Education in lnner Mongolia Autonomous Region,Baotou Teachers’College,Baotou 014030,China [5]Beijing National Laboratory for Condensed Matter Physics and Laboratory of Soft Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [6]University of Chinese Academy of Sciences,Beijing 100049,China [7]Songshan Lake Materials Laboratory,Dongguan 523808,China

出　　处：《Chinese Physics B》2025年第4期598-603,共6页中国物理B(英文版)

基　　金：supports of the National Natural Science Foundation of China(Grant Nos.12304245,12374205,12475031,and 12364029);the Science Foundation of China University of Petroleum,Beijing(Grant Nos.2462023YJRC031 and 2462024BJRC010);the National Key Laboratory of Petroleum Resources and Engineering(Grant No.PRE/DX-2407);the Natural Science Foundation of Shandong Province(Grant No.ZR2024YQ017);the Young Elite Scientist Sponsorship Program by BAST(Grant No.BYESS2023300);the Beijing Institute of Technology Research Fund Program for Young Scholars;This work was also supported by Beijing National Laboratory for Condensed Matter Physics(Grant Nos.2023BNLCMPKF014 and 2024BNLCMPKF009).

摘　　要：We conduct optical-tweezers experiments to investigate the average potential energies of passive plates harmonically trapped in bacterial suspensions.Our results show that the mean potential energies along both the major and minor axes increase with bacterial concentration but decrease with trap stiffness.Notably,the average potential energy along the major axis consistently exceeds that along the minor axis.This discrepancy from equilibrium systems is primarily attributed to the distinct bacterial flow fields and direct bacterium–plate collisions near the major and minor axes,as evidenced by the higher orientational order around the plate along the major compared to the minor axis,despite identical bacterial densities in these regions.Our findings highlight the critical role of hydrodynamic interactions in determining the potential energy of passive objects immersed in an active bath.

关 键 词：average potential energy active bath passive plate hydrodynamic interactions 

分 类 号：O35[理学—流体力学]