Direct Evidence of Void-Induced Structural Relaxations in Colloidal Glass Formers
| Autor: | Chi Hang Lam, Masaharu Isobe, Yuen Hong Tsang, Simiao Ren, Yilong Han, Kin Ping Wong, Cho Tung Yip, Qingxiao Huo, Chun Shing Lee, Chor-Hoi Chan |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Condensed Matter - Materials Science
Void (astronomy) Materials science Direct evidence Dispersity Materials Science (cond-mat.mtrl-sci) FOS: Physical sciences General Physics and Astronomy Disordered Systems and Neural Networks (cond-mat.dis-nn) Condensed Matter - Soft Condensed Matter Condensed Matter - Disordered Systems and Neural Networks Condensed Matter::Disordered Systems and Neural Networks 01 natural sciences Condensed Matter::Soft Condensed Matter Colloid Chemical physics Particle dynamics Vacancy defect 0103 physical sciences Soft Condensed Matter (cond-mat.soft) 010306 general physics Supercooling |
| Zdroj: | Physical Review Letters. 125 |
| ISSN: | 1079-7114 0031-9007 |
| DOI: | 10.1103/physrevlett.125.258001 |
| Popis: | Particle dynamics in supercooled liquids are often dominated by string-like 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 string-like motions. In the glass, a void takes the form of a quasi-void consisting of a few neighboring free volumes and is transported by the string-like motions it induces. In fully glassy systems with a large polydispersity, similar quasi-void actions are observed. The mobile particles cluster into string-like or compact geometries, but the compact ones can further be broken down into connected sequences of strings, establishing their general importance. main text 5 pages 4 figures + supplymentary material 24 pages 23 figures (Ancillary files), 2020 Nov accepted by Physical Review Letter |
| Databáze: | OpenAIRE |
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