Non-phononic density of states of two-dimensional glasses revealed by random pinning

Abstract

The vibrational density of states of glasses is considerably different from that of crystals. In particular, there exist spatially localized vibrational modes in glasses. The density of states of these non-phononic modes has been observed to follow $g(\omega )\propto {\omega }^4$, where $\omega$ is the frequency. However, in two-dimensional systems, the abundance of phonons makes it difficult to accurately determine this non-phononic density of states because they are strongly coupled to non-phononic modes and yield strong system-size and preparation-protocol dependencies. In this article, we utilize the random pinning method to suppress phonons and disentangle their coupling with non-phononic modes and successfully calculate their density of states as $g(\omega )\propto {\omega }^4$. We also study their localization properties and confirm that low-frequency non-phononic modes in pinned systems are truly localized without far-field contributions. We finally discuss the excess density of states over the Debye value that results from the hybridization of phonons and non-phononic modes.

6 pages, 3 figures

References in corpus (17)

• Universality of the nonphononic vibrational spectrum across different classes of computer glasses
• Acoustic excitations and elastic heterogeneities in disordered solids
• Low-frequency vibrational spectrum of mean-field disordered systems
• Elastic moduli fluctuations predict wave attenuation rates in glasses
• Universal low-frequency vibrational modes in silica glasses
• Low-frequency vibrations of jammed packings in large spatial dimensions
• Finite-size effects in the nonphononic density of states in computer glasses
• Low-frequency excess vibrational modes in two-dimensional glasses
• Marginal stability of soft anharmonic mean field spin glasses
• Nonphononic spectrum of two-dimensional structural glasses
• Scaling of the Non-Phononic Spectrum of Two-Dimensional Glasses
• Low-Frequency Vibrational States in Ideal Glasses with Random Pinning
• Mechanical and Vibrational Properties of Three-Dimensional Dimer Packings Near the Jamming Transition
• Random quench predicts universal properties of amorphous solids
• Sound damping in frictionless granular materials: The interplay between configurational disorder and inelasticity
• Quasi-localized vibrational modes, Boson peak and sound attenuation in model mass-spring networks
• Novel elastic instability of amorphous solids in finite spatial dimensions

Cited by in corpus (6)

• Experimental evidence for the ${\omega }^4$ tail of the nonphononic spectra of glasses
• Testing the Heterogeneous-Elasticity Theory for low-energy excitations in structural glasses
• Enumerating low-frequency nonphononic vibrations in computer glasses
• Unified study of viscoelasticity and sound damping in hard and soft amorphous solids
• Critical fluctuations of elastic moduli in jammed solids
• Particle pinning as a method to manipulate marginal stability