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Fluctuation dissipation ratio in an aging Lennard-Jones glass

Jean-Louis Barrat·Walter Kob
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Abstract

By using extensive Molecular Dynamics simulations, we have determined the violation of the fluctuation-dissipation theorem in a Lennard-Jones liquid quenched to low temperatures. For this we have calculated $X(C)$, the ratio between a one particle time-correlation function $C$ and the associated response function. Our results are best fitted by assuming that $X(C)$ is a discontinuous, piecewise constant function. This is similar to what is found in spin systems with one step replica symmetry breaking. This strengthen the conjecture of a similarity between the phase space structure of structural glasses and such spin systems.

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BibTeXRIS

Jean-Louis Barrat, Walter Kob. 1998-09-21. Fluctuation dissipation ratio in an aging Lennard-Jones glass. https://doi.org/10.1209/epl%2Fi1999-00313-4

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