# Buckling of self-assembled colloidal structures

## TL;DR

This study explores the buckling behavior of self-assembled colloidal chains, revealing the influence of thermal fluctuations and plasticity on their mechanical stability, which advances understanding of complex colloidal structures.

## Contribution

It provides the first detailed analysis of buckling in colloidal chains, highlighting the roles of thermal fluctuations and plastic effects in their nonlinear mechanics.

## Key findings

- Fluctuations diverge near buckling onset.
- Plasticity influences buckling dynamics at large deformations.
- Buckling behavior resembles classical Euler buckling with added thermal and plastic effects.

## Abstract

Although buckling is a prime route to achieve functionalization and synthesis of single colloids, buckling of colloidal structures---made up of multiple colloids---remains poorly studied. Here, we investigate the buckling of the simplest form of a colloidal structure, a colloidal chain that is self-assembled through critical Casimir forces. We demonstrate that the mechanical instability of such a chain is strikingly reminiscent of that of classical Euler buckling but with thermal fluctuations and plastic effects playing a significant role. Namely, we find that fluctuations tend to diverge close to the onset of buckling and that plasticity controls the buckling dynamics at large deformations. Our work provides insight into the effect of geometrical, thermal and plastic interactions on the nonlinear mechanics of self-assembled structures, of relevance for the rheology of complex and living matter and the rational design of colloidal architectures.