Direct measurements of the dynamical correlation length indicate its divergence at an athermal glass transition

Abstract

The super-cooled $N3$ model exhibits an increasingly slow dynamics as density approaches the model's random closest packing density. Here, we present a direct measurement of the dynamical correlation function $G_4(r,t)$, showing the emergence of a growing length scale ${\xi }_4$ across which the dynamics is correlated. The correlation length measured, up to 120 lattice sites, power-law diverges as the density approaches ${\rho }_t$, the density at which the fluid phase of the model is predicted to terminate. It is shown that the four-point susceptibility, often used as an agent to estimate ${\xi }_4$, does not depend simply on the latter. Rather, it depends strongly on the short-range behavior of $G_4(r,t)$. Consequently, ${\chi }_4$ peaks before ${\xi }_4$ reaches its maximal value. The two quantities should therefore be studied independently.

5 pages 5 figures

References in corpus (4)

• Supercooled Liquids for Pedestrians
• Inhomogeneous Mode-Coupling Theory and Growing Dynamic Length in Supercooled Liquids
• Growing length and time scales in glass forming liquids
• The building blocks of dynamical heterogeneities in dense granular media