Long-wavelength fluctuations and anomalous dynamics in two-dimensional liquids

Abstract

Long-wavelength Mermin-Wagner fluctuations prevent the existence of translational long-range order, in two-dimensional systems at finite temperature. Their dynamical signature, which is the divergence of the vibrational amplitude with the system size, also affects disordered solids and washes out the transient solid-like response generally exhibited by liquids cooled below their melting temperature. Through a combined numerical and experimental investigation, here we show that long-wavelength fluctuations are also relevant at high temperature, where the liquid dynamics does not reveal a transient solid-like response. In this regime, they induce an unusual but ubiquitous decoupling between long-time diffusion coefficient $D$ and structural relaxation time $\tau$, where $D\propto {\tau }^{-\kappa }$, with $\kappa >1$. Long-wavelength fluctuations have a negligible influence on the relaxation dynamics only at extremely high temperatures, in molecular liquids, or extremely low densities, in colloidal systems.

References in corpus (14)

• Jamming at Zero Temperature and Zero Applied Stress: the Epitome of Disorder
• Scaling behavior in the $\beta$-relaxation regime of a supercooled Lennard-Jones mixture
• Irreversible reorganization in a supercooled liquid originates from localised soft modes
• GALAMOST: GPU-accelerated large-scale molecular simulation toolkit
• Mermin-Wagner fluctuations in 2D amorphous solids
• Fundamental differences between glassy dynamics in two and three dimensions
• Brownian motion at short time scales
• Breakdown of the Stokes-Einstein relation in two, three and four dimensions
• Long Wavelength Fluctuations and the Glass Transition in 2D and 3D
• Identifying time scales for violation/preservation of Stokes-Einstein relation in supercooled water
• Unveiling Dimensionality Dependence of Glassy Dynamics: 2D Infinite Fluctuation Eclipses Inherent Structural Relaxation
• Shape of Dynamical Heterogeneities and the Stokes-Einstein and Stokes-Einstein-Debye Relations in Suspensions of Colloidal Ellipsoids
• Viscoelastic shear stress relaxation in two-dimensional glass forming liquids
• Local Density Fluctuation Governs the Divergence of Viscosity underlying Elastic and Hydrodynamic Anomalies in a 2D Glass-Forming Liquid

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• Characterising the slow dynamics of the swap Monte Carlo algorithm
• Revealing the Geometrical and Vibrational Properties of the Defects Driving the Boson Peak
• Atomistic mechanisms of dynamics in a two-dimensional dodecagonal quasicrystal
• Long-wavelength fluctuations and dimensionality crossover in confined liquids
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• Non-Gaussian Rotational Diffusion and Swing Motion of Dumbbell Probes in Two Dimensional Colloids