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arXiv · 2003.07614

Universal low-frequency vibrational modes in silica glasses

Silvia Bonfanti·Roberto Guerra·Chandana Mondal·Itamar Procaccia·Stefano Zapperi
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Abstract

It was recently shown that different simple models of glass formers with binary interactions define a universality class in terms of the density of states of their quasi-localized low-frequency modes. Explicitly, once the hybridization with standard Debye (extended) modes is avoided, a number of such models exhibit a universal density of state, depending on the mode frequencies as $D(\omega) \sim \omega^4$. It is unknown however how wide is this universality class, and whether it also pertains to more realistic models of glass formers. To address this issue we present analysis of the quasi-localized modes in silica, a network glass which has both binary and ternary interactions. We conclude that in 3-dimensions silica exhibits the very same frequency dependence at low frequencies, suggesting that this universal form is a generic consequence of amorphous glassiness.

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Silvia Bonfanti, Roberto Guerra, Chandana Mondal, Itamar Procaccia, Stefano Zapperi. 2020-03-17. Universal low-frequency vibrational modes in silica glasses. https://doi.org/10.1103/physrevlett.125.085501

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