Anomalous phonon scattering and elastic correlations in amorphous solids

A major issue in materials science is why glasses present low-temperature thermal and vibrational properties that sharply differ from those of crystals. In particular, long-wavelength phonons are considerably more damped in glasses, yet it remains unclear how structural disorder at atomic scales aff...

Full description

Saved in:
Bibliographic Details
Published in:Nature materials 2016-11, Vol.15 (11), p.1177-1181
Main Authors: Gelin, Simon, Tanaka, Hajime, Lemaître, Anaël
Format: Article
Language:English
Subjects:
639/301/1034/1035
639/301/1034/1039
639/301/923/218
639/766/119/1002
Amorphous materials
Biomaterials
Condensed Matter Physics
Correlation
Crystals
Damping
Elastic scattering
Elasticity
Low temperature
Materials Science
Nanotechnology
Optical and Electronic Materials
Phonons
Rayleigh scattering
Wavelengths
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A major issue in materials science is why glasses present low-temperature thermal and vibrational properties that sharply differ from those of crystals. In particular, long-wavelength phonons are considerably more damped in glasses, yet it remains unclear how structural disorder at atomic scales affects such a macroscopic phenomenon. A plausible explanation is that phonons are scattered by local elastic heterogeneities that are essentially uncorrelated in space, a scenario known as Rayleigh scattering, which predicts that the damping of acoustic phonons scales with wavenumber k as k d +1 (in dimension d ). Here we demonstrate that phonon damping scales instead as − k d +1  ln  k , with this logarithmic enhancement originating from long-range spatial correlations of elastic disorder caused by similar stress correlations. Our work suggests that the presence of long-range spatial correlations of local stress and elasticity may well be the crucial feature that distinguishes amorphous solids from crystals. Studies of the phonon damping mechanism in glasses reveal scaling with the wavevector k which is different from the traditionally assumed Rayleigh scattering. These findings are related to long-range correlations in the local stress.
ISSN:1476-1122
1476-4660
DOI:10.1038/nmat4736