中国物理B ›› 2020, Vol. 29 ›› Issue (5): 58201-058201.doi: 10.1088/1674-1056/ab7d9b

所属专题: SPECIAL TOPIC — Active matters physics

• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇    下一篇

Constraint dependence of average potential energy of a passive particle in an active bath

Simin Ye(叶思敏), Peng Liu(刘鹏), Zixuan Wei(魏子轩), Fangfu Ye(叶方富), Mingcheng Yang(杨明成), Ke Chen(陈科)   

  1. 1 Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    2 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China;
    3 Songshan Lake Materials Laboratory, Dongguan 523808, China;
    4 Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325001, China
  • 收稿日期:2020-01-08 修回日期:2020-02-27 出版日期:2020-05-05 发布日期:2020-05-05
  • 通讯作者: Fangfu Ye, Mingcheng Yang, Ke Chen E-mail:fye@iphy.ac.cn;mcyang@iphy.ac.cn;kechen@iphy.ac.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11874397, 11674365, 11774393, and 11774394).

Constraint dependence of average potential energy of a passive particle in an active bath

Simin Ye(叶思敏)1,2, Peng Liu(刘鹏)1,2, Zixuan Wei(魏子轩)2, Fangfu Ye(叶方富)1,2,3,4, Mingcheng Yang(杨明成)1,2, Ke Chen(陈科)1,2,3   

  1. 1 Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    2 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China;
    3 Songshan Lake Materials Laboratory, Dongguan 523808, China;
    4 Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325001, China
  • Received:2020-01-08 Revised:2020-02-27 Online:2020-05-05 Published:2020-05-05
  • Contact: Fangfu Ye, Mingcheng Yang, Ke Chen E-mail:fye@iphy.ac.cn;mcyang@iphy.ac.cn;kechen@iphy.ac.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11874397, 11674365, 11774393, and 11774394).

摘要: We quantify the mean potential energy of a passive colloidal particle harmonically confined in a bacterial solution using optical traps. We find that the average potential energy of the passive particle depends on the trap stiffness, in contrast to the equilibrium case where energy partition is independent of the external constraints. The constraint dependence of the mean potential energy originates from the fact that the persistent collisions between the passive particle and the active bacteria are influenced by the particle relaxation dynamics. Our experimental results are consistent with the Brownian dynamics simulations, and confirm the recent theoretical prediction.

关键词: constraint dependence, average potential energy, active bath, passive tracer, optical trap

Abstract: We quantify the mean potential energy of a passive colloidal particle harmonically confined in a bacterial solution using optical traps. We find that the average potential energy of the passive particle depends on the trap stiffness, in contrast to the equilibrium case where energy partition is independent of the external constraints. The constraint dependence of the mean potential energy originates from the fact that the persistent collisions between the passive particle and the active bacteria are influenced by the particle relaxation dynamics. Our experimental results are consistent with the Brownian dynamics simulations, and confirm the recent theoretical prediction.

Key words: constraint dependence, average potential energy, active bath, passive tracer, optical trap

中图分类号:  (Colloids)

  • 82.70.Dd
05.40.-a (Fluctuation phenomena, random processes, noise, and Brownian motion) 47.63.Gd (Swimming microorganisms)