Elastic behavior in a supercooled liquid: analysis of viscoelasticity using an extended mode coupling model

The transverse current correlations are analyzed using the formalism of extended mode coupling theory. The undercooled liquid can sustain shear waves up to a minimum wave number. With the increase of density this wave number decreases, indicating a growing length scale that is related to the dynamics. The speed of the propagating shear waves goes to zero approaching a critical wave number. The maximum wavelength shows an initial enhancement approaching the mode coupling transition and finally grows at a slower rate as the sharp transition is cut off.