Diffusion mechanisms in metallic supercooled liquids and glasses
Abstract
The mechanisms of atomic transport in supercooled liquids and the nature of the glass transition are long-standing problems. Collective atomic motion is thought to play an important role in both phenomena. A metallic supercooled liquid represents an ideal system for studying intrinsic collective motions because of its structural similarity to the "dense random packing of spheres" model, which is conceptually simple. Unlike polymeric and network glasses, metallic supercooled liquids have only recently become experimentally accessible, following the discovery of bulk metallic glasses. Here we report a ⁹Be nuclear magnetic resonance study of Zr-based bulk metallic glasses in which we investigate microscopic transport in supercooled liquids around the glass transition regime. Combining our results with diffusion measurements, we demonstrate that two distinct processes contribute to long-range transport in the supercooled liquid state: single-atom hopping and collective motion, the latter being the dominant process. The effect of the glass transition is clearly visible in the observed diffusion behaviour of the Be atoms.
Additional Information
This work was supported by the US Army Research Office, the US National Science Foundation, and the US Department of Energy.Additional details
- Eprint ID
- 120770
- Resolver ID
- CaltechAUTHORS:20230412-407799000.2
- Army Research Office (ARO)
- NSF
- Department of Energy (DOE)
- Created
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2023-04-13Created from EPrint's datestamp field
- Updated
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2023-04-13Created from EPrint's last_modified field