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Role of the unstable directions in the equilibrium and aging dynamics of supercooled liquids

Claudio Donati·Francesco Sciortino·Piero Tartaglia
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Abstract

The connectivity of the potential energy landscape in supercooled atomic liquids is investigated through the calculation of the instantaneous normal modes spectrum and a detailed analysis of the unstable directions in configuration space. We confirm the hypothesis that the mode-coupling critical temperature is the $T$ at which the dynamics crosses over from free to activated exploration of configuration space. We also report the observed changes in the local connectivity of configuration space sampled during aging, following a temperature jump from a liquid to a glassy state.

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Claudio Donati, Francesco Sciortino, Piero Tartaglia. 2000-07-12. Role of the unstable directions in the equilibrium and aging dynamics of supercooled liquids. https://doi.org/10.1103/physrevlett.85.1464

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