TY - JOUR
T1 - Interparticle Adhesion Regulates the Surface Roughness of Growing Dense Three-Dimensional Active Particle Aggregates
AU - Sinha, Sumit
AU - Malmi-Kakkada, Abdul N.
N1 - Funding Information:
We would like to thank Prof. D. Thirumalai for discussions. We would also like to thank Xin Li and Himadri Samanta for their inputs during the course of this work. This work was supported by grants from the National Science Foundation (Grants PHY 17-08128 and PHY-1522550). A.N.M.-K. acknowledges funding support from the College of Science and Mathematics at Augusta University.
Publisher Copyright:
© 2021 American Chemical Society.
PY - 2021/9/9
Y1 - 2021/9/9
N2 - Activity and self-generated motion are fundamental features observed in many living and nonliving systems. Given that interparticle adhesive forces can regulate particle dynamics, we investigate how interparticle adhesion strength controls the boundary growth and roughness of active particle aggregates. Using particle based simulations incorporating both activity (birth, death, and growth) and systematic physical interactions (elasticity and adhesion), we establish that interparticle adhesion strength (fad) controls the surface roughness of a densely packed three-dimensional(3D) active particle aggregate expanding into a highly viscous medium. We discover that the surface roughness of a 3D active particle aggregate increases in proportion to the interparticle adhesion strength (fad) and show that asymmetry in the radial and transverse active particle mean-squared displacement (MSD) suppresses 3D surface roughness at lower adhesion strengths. By analyzing the statistical properties of particle displacements at the aggregate periphery, we determine that the 3D surface roughness is driven by the movement of active particle toward the core at high interparticle adhesion strengths. Our results elucidate the physics controlling the expansion of adhesive 3D active particle collectives into a highly viscous medium, with implications into understanding stochastic interface growth in active matter systems characterized by self-generation of particles.
AB - Activity and self-generated motion are fundamental features observed in many living and nonliving systems. Given that interparticle adhesive forces can regulate particle dynamics, we investigate how interparticle adhesion strength controls the boundary growth and roughness of active particle aggregates. Using particle based simulations incorporating both activity (birth, death, and growth) and systematic physical interactions (elasticity and adhesion), we establish that interparticle adhesion strength (fad) controls the surface roughness of a densely packed three-dimensional(3D) active particle aggregate expanding into a highly viscous medium. We discover that the surface roughness of a 3D active particle aggregate increases in proportion to the interparticle adhesion strength (fad) and show that asymmetry in the radial and transverse active particle mean-squared displacement (MSD) suppresses 3D surface roughness at lower adhesion strengths. By analyzing the statistical properties of particle displacements at the aggregate periphery, we determine that the 3D surface roughness is driven by the movement of active particle toward the core at high interparticle adhesion strengths. Our results elucidate the physics controlling the expansion of adhesive 3D active particle collectives into a highly viscous medium, with implications into understanding stochastic interface growth in active matter systems characterized by self-generation of particles.
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U2 - 10.1021/acs.jpcb.1c02758
DO - 10.1021/acs.jpcb.1c02758
M3 - Article
C2 - 34499496
AN - SCOPUS:85115664284
SN - 1520-6106
VL - 125
SP - 10445
EP - 10451
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 37
ER -