Anomalous Phonon Behavior: Blueshift of the Surface Boson Peak in Silica Glass with Increasing Temperature
نویسندگان
چکیده
منابع مشابه
Anomalous phonon behavior: blueshift of the surface boson peak in silica glass with increasing temperature.
We present helium atom scattering measurements of the boson peak at the surface of vitreous silica between 127.0 and 368.5 K. The most probable energy shows a strong temperature dependence and increases linearly with temperature in the measured range. The observed blueshift of the surface boson peak (shift rate 0.008+/-0.002 meV/K) is a factor of 4 to 10 times stronger than shift rates measured...
متن کاملAnomalous diffusion in heterogeneous glass-forming liquids: temperature-dependent behavior.
In a preceding paper, Langer and Mukhopadhyay [Phys. Rev. E 77, 061505 (2008)] studied the diffusive motion of a tagged molecule in an heterogeneous glass-forming liquid at temperatures just above a glass transition. Among other features of this system, we postulated a relation between heterogeneity and stretched-exponential decay of correlations, and we also confirmed that systems of this kind...
متن کاملObservation of the boson peak at the surface of vitreous silica.
The boson peak is an excess in the phonon density of states compared to the Debye model that appears in almost all glasses. It has been repeatedly measured in the bulk by a variety of methods, but its origin is still highly debated. Here we present first experimental evidence of the boson peak on the v-SiO2 surface. The measurements were obtained by helium atom scattering. The boson peak appear...
متن کاملScaling the temperature-dependent boson peak of vitreous silica with the high-frequency bulk modulus derived from Brillouin scattering data.
The position and strength of the boson peak in silica glass vary considerably with temperature T. Such variations cannot be explained solely with changes in the Debye energy. New Brillouin-scattering measurements are presented which allow determining the T dependence of unrelaxed acoustic velocities. Using a velocity based on the bulk modulus, scaling exponents are found which agree with the so...
متن کاملBoson peak and terahertz frequency dynamics of vitreous silica
This paper describes the progress that has been made in the past decade in the investigation of the peculiar dynamic properties of vitreous silica (v-SiO2) and related glasses in the terahertz (THz) frequency range. The reason why we focus our attention on v-SiO2 is that it is one of the principal network glasses and exhibits all features typical of glasses. These are the increased inelastic sc...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2008
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.100.135504