Local Density Fluctuation Governs the Divergence of Viscosity underlying Elastic and Hydrodynamic Anomalies in a 2D Glass-Forming Liquid

Hayato Shiba; Takeshi Kawasaki; Kang Kim

doi:10.1103/physrevlett.123.265501

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arXiv · 1905.05458

Local Density Fluctuation Governs the Divergence of Viscosity underlying Elastic and Hydrodynamic Anomalies in a 2D Glass-Forming Liquid

Hayato Shiba·Takeshi Kawasaki·Kang Kim

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Abstract

If a liquid is cooled rapidly to form a glass, its structural relaxation becomes retarded, producing a drastic increase in viscosity. In two dimensions, strong long-wavelength fluctuations persist, even at low temperature, making it difficult to evaluate the microscopic structural relaxation time. This Letter shows that, in a 2D glass-forming liquid, relative displacement between neighbor particles yields a relaxation time that grows in proportion to the viscosity. In addition to thermal elastic vibrations, hydrodynamic fluctuations are found to affect the long-wavelength dynamics, yielding a logarithmically diverging diffusivity in the long-time limit.

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Hayato Shiba, Takeshi Kawasaki, Kang Kim. 2019-12-24. Local Density Fluctuation Governs the Divergence of Viscosity underlying Elastic and Hydrodynamic Anomalies in a 2D Glass-Forming Liquid. https://doi.org/10.1103/physrevlett.123.265501

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