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arXiv · 1108.2636

Glass elasticity from particle trajectories

Christian L. Klix·Florian Ebert·Fabian Weysser·Matthias Fuchs·Georg Maret·Peter Keim
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Abstract

Using positional data from video-microscopy of a two-dimensional colloidal system and from simulations of hard discs we determine the wave-vector-dependent normal mode spring constants in the supercooled fluid and glassy state, respectively. The emergence of rigidity and the existence of a displacement field in amorphous solids is clarified. Continuum elastic theory is used in the limit of long wavelengths to analyze the bulk and shear modulus of this amorphous system as a function of temperature. The onset of a finite static shear modulus upon cooling marks the fluid/solid transition. This provides an opportunity to determine the glass transition temperature $T_g$ in an intuitive and precise way.

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Christian L. Klix, Florian Ebert, Fabian Weysser, Matthias Fuchs, Georg Maret, Peter Keim. 2012-10-02. Glass elasticity from particle trajectories. https://doi.org/10.1103/physrevlett.109.178301

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