Slow Relaxation and Landscape-Driven Dynamics in Viscous Ripening Foams

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Thirumalaiswamy, Amruthesh, Rodríguez-Cruz, Clary, Riggleman, Robert A., Crocker, John C.
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915418962132992
author Thirumalaiswamy, Amruthesh
Rodríguez-Cruz, Clary
Riggleman, Robert A.
Crocker, John C.
author_facet Thirumalaiswamy, Amruthesh
Rodríguez-Cruz, Clary
Riggleman, Robert A.
Crocker, John C.
contents Foams and dense emulsions display complex mechanical behavior, including intermittent rearrangement dynamics, power-law rheology, and slow recovery after perturbation. These effects have long been considered evidence for glassy physics in these and other materials having similar mechanics, such as the cytoskeleton. Here we study such anomalous mechanics in a simulated wet foam driven by ripening and find behavior that has a different physical origin than that in glasses. Rather, the dynamics is due to a balance of forces from the system's self-similar potential energy landscape and viscous stress. At the lowest viscosities, bubbles move intermittently, with the system shifting abruptly between shallow potential energy minima. For higher viscosities, in contrast, the bubbles move continuously and the system follows a tortuous, fractal path through high-dimensional configuration space, at higher mean energy than the lower viscosity case. The long-time dynamics and power-law rheology are the direct consequence of the potential energy landscape's self-similar geometry. Lastly, we find that the slow recovery of perturbed foams is due to the foam being kinetically rather than energetically trapped in high-energy portions of the energy landscape. Overall, viscous ripening foams follow a biased energy minimization pathway that explores regions of the energy landscape that are qualitatively different (flatter and smoother) than those corresponding to well-annealed glasses.
format Preprint
id arxiv_https___arxiv_org_abs_2301_13400
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Slow Relaxation and Landscape-Driven Dynamics in Viscous Ripening Foams
Thirumalaiswamy, Amruthesh
Rodríguez-Cruz, Clary
Riggleman, Robert A.
Crocker, John C.
Soft Condensed Matter
Foams and dense emulsions display complex mechanical behavior, including intermittent rearrangement dynamics, power-law rheology, and slow recovery after perturbation. These effects have long been considered evidence for glassy physics in these and other materials having similar mechanics, such as the cytoskeleton. Here we study such anomalous mechanics in a simulated wet foam driven by ripening and find behavior that has a different physical origin than that in glasses. Rather, the dynamics is due to a balance of forces from the system's self-similar potential energy landscape and viscous stress. At the lowest viscosities, bubbles move intermittently, with the system shifting abruptly between shallow potential energy minima. For higher viscosities, in contrast, the bubbles move continuously and the system follows a tortuous, fractal path through high-dimensional configuration space, at higher mean energy than the lower viscosity case. The long-time dynamics and power-law rheology are the direct consequence of the potential energy landscape's self-similar geometry. Lastly, we find that the slow recovery of perturbed foams is due to the foam being kinetically rather than energetically trapped in high-energy portions of the energy landscape. Overall, viscous ripening foams follow a biased energy minimization pathway that explores regions of the energy landscape that are qualitatively different (flatter and smoother) than those corresponding to well-annealed glasses.
title Slow Relaxation and Landscape-Driven Dynamics in Viscous Ripening Foams
topic Soft Condensed Matter
url https://arxiv.org/abs/2301.13400