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Title: Behavior-dependent critical dynamics in collective states of active particles
Abstract We experimentally demonstrate critical collective behavior in a system of active colloidal particles (APs), achieved through variations of their mutual interactions using feedback control. At the transition between a swarm and a swirl we observe an explicit bifurcation dynamics of the rotational order parameter and a critical slowing down, i.e. , a growth of the relaxation time by almost one order of magnitude. Additional signatures of critical dynamics, including hysteresis in presence of symmetry-breaking particle interactions, and a maximum of the susceptibility, are measured and characterized in terms of a theoretical model which is based purely on the time-reversal symmetry of the order parameter.  more » « less
Award ID(s):
1708280
PAR ID:
10356232
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Europhysics Letters
Volume:
134
Issue:
6
ISSN:
0295-5075
Page Range / eLocation ID:
64001
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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