Seminario virtuale: Universal Low-Frequency Vibrational Modes in Silica Glasses
Tuesday 15 September 2020, 14.00
on zoom: https://lmu-munich.zoom.us/j/95015174315?pwd=MHpRTXRwQ1Rpc2R0MkJHNEh0OEM2QT09
Universal Low-Frequency Vibrational Modes in Silica Glasses
Silvia Bonfanti, University of Milan
ABSTRACT: Universality of glassy vibrational modes in simple models of glass formers with binary interactions has been recently discovered.
Explicitly, once the hybridization with standard Debye modes is avoided, a number of such models show a universal density of states,
that depend on the mode frequencies as D(\omega) \sim \omega^4. However it is unknown how wide this universality class is,
and especially whether includes more realistic model of glasses. We address this issue analyzing the quasilocalized modes
in a realistic model of amorphous silica that has both binary and ternary interactions and find the very same frequency dependence
at low frequencies, suggesting that this universal form is a generic consequence of amorphous glassiness.