Direct Evidence of Void-Induced Structural Relaxations in Colloidal Glass Formers

Cho Tung Yip, Masaharu Isobe, Chor Hoi Chan, Simiao Ren, Kin Ping Wong, Qingxiao Huo, Chun Shing Lee, Yuen Hong Tsang, Yilong Han, Chi Hang Lam

Research output: Journal article publicationJournal articleAcademic researchpeer-review

2 Citations (Scopus)

Abstract

Particle dynamics in supercooled liquids are often dominated by stringlike motions in which lines of particles perform activated hops cooperatively. The structural features triggering these motions, crucial in understanding glassy dynamics, remain highly controversial. We experimentally study microscopic particle dynamics in colloidal glass formers at high packing fractions. With a small polydispersity leading to glass-crystal coexistence, a void in the form of a vacancy in the crystal can diffuse reversibly into the glass and further induces stringlike motions. In the glass, a void takes the form of a quasivoid consisting of a few neighboring free volumes and is transported by the stringlike motions it induces. In fully glassy systems with a large polydispersity, similar quasivoid actions are observed. The mobile particles cluster into stringlike or compact geometries, but the compact ones can be further broken down into connected sequences of strings, establishing their general importance.

Original languageEnglish
Article number258001
JournalPhysical Review Letters
Volume125
Issue number25
DOIs
Publication statusPublished - 17 Dec 2020

ASJC Scopus subject areas

  • Physics and Astronomy(all)

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