Abstract
A hallmark of glasses is an excess of low-frequency, nonphononic vibrations. It is manifested as a terahertz peak - the boson peak - in the ratio of the vibrational density of state (VDoS) and Debye's VDoS of phonons. Here, using experimental data, extensive computer simulations, and a mean-field model, we show that the nonphononic part of the VDoS itself features both a universal power-law tail and a peak at higher frequencies, entirely accounted for by quasilocalized nonphononic vibrations, whose existence and spectra power-law tail were recently established in computer glasses. We rationalize the variation of the peak's frequency and magnitude with glasses' thermal history, which is much weaker than the variation of the tail and may follow an opposite trend, and show that the peak's modes are composed of many spatially coupled quasilocalized nonphononic vibrations. Our results shed light on the origin, nature, and properties of the boson peak in glasses.
| Original language | English |
|---|---|
| Article number | 023053 |
| Journal | Physical Review Research |
| Volume | 6 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Apr 2024 |
Bibliographical note
A.M. acknowledges support from the Minerva center on “Aging, from physical materials to human tissues.” E.L. acknowledges support from The Dutch Research Council (Vidi Grant No. 680-47-554/3259). E.B. acknowledges support from the Ben May Center for Chemical Theory and Computation and the Harold Perlman Family.Publisher Copyright:
© 2024 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
All Science Journal Classification (ASJC) codes
- General Physics and Astronomy