Non-linear rheology of layered systems - a phase model approach

TL;DR

This paper investigates the non-linear rheology of layered systems using a 2D phase model, revealing a transition from Newtonian to shear-thinning behavior related to dislocation dynamics and a Kosterlitz-Thouless transition.

Contribution

It introduces a 2D phase model capturing non-linear rheology and dislocation-driven shear thinning in layered systems, linking it to topological phase transitions.

Findings

System behaves as Newtonian fluid above Tc

Exhibits shear thinning below Tc

Dislocation motions resemble vortex dynamics in superconductors

Abstract

We study non-linear rheology of a simple theoretical model developed to mimic layered systems such as lamellar structures under shear. In the present work we study a 2-dimensional version of the model which exhibits a Kosterlitz-Thouless transition in equilibrium at a critical temperature Tc. While the system behaves as Newtonain fluid at high temperatures T > Tc, it exhibits shear thinning at low temperatures T < Tc. The non-linear rheology in the present model is understood as due to motions of edge dislocations and resembles the non-linear transport phenomena in superconductors by vortex motions.