This review covers a wide range of experimental and theoretical studies of two-level or
tunnelling states in glasses. Emphasis is on fundamental physics rather than a detailed …

This article is a review of the dissipation processes in nanoelectromechanical systems
(NEMS). As NEMS technology becomes more and more prevalent in research and …

The various origins of a frequency-dependent conductivity in amorphous semiconductors
are reviewed, stressing particularly recent advances and the influences that factors such as …

Non-crystalline solid tellurite glasses continue to intrigue both academic and industry
researchers not only because of their many technical applications, but also because of a …

In order to test whether the low-energy excitations explored extensively in amorphous solids
are indeed universal, all measurements published on the low-temperature thermal …

Many features of glasses below 1 K are explicable in terms of localized tunneling levels, for
which a spin-1 2 analogy exists. Here we show that spectral diffusion, resulting from …

A new model for the relaxation of a potential perturbation in dielectric materials is developed
based on the correlated properties of a two-level system containing two types of decay …

Surveys the developments in Brillouin scattering during the past fifteen years. Mainly
classical effects are described, therefore excluding stimulated and resonance Brillouin …

Surveys the contemporary concepts and theoretical and experimental results of tunneling
processes. Examines from a unified viewpoint not only chemical reactions but also other …

The propagation and damping of the acoustic excitations in vitreous silica is measured at
terahertz frequencies using inelastic x-ray scattering. The apparent sound velocity shows a …