Amorphous solids show surprisingly universal behaviour at low temperatures. The
prevailing wisdom is that this can be explained by the existence of two-state defects within …

Amorphous solids fall into any reasonable definition of a solid. This means that it should be
possible to describe amorphous solids in terms of an expansion in deviations from a well …

The interaction of sound waves with tunneling, relaxational, and resonant vibrational states
in glasses is investigated within the soft-potential model. The same bilinear coupling …

We show that a vibrational instability of the spectrum of weakly interacting quasilocal
harmonic modes creates the maximum in the inelastic scattering intensity in glasses, the …

The soft-potential model (an extension of the well-known tunneling model for two-level
states in glasses) has been formulated in terms of soft-mode eigenvectors in order to …

We show that the same physical mechanism is fundamental for two seemingly different
phenomena such as the formation of two-level systems in glasses and the boson peak in the …

The soft potential model (an extension of the tunneling model to include soft localized
vibrations) is shown to describe the anomalous features of the specific heat CP and the …

We consider classical normal modes and noninteracting bosonic excitations in disordered
systems. We emphasize generic aspects of such problems and parallels with disordered …

Previous simulation studies of localized low-frequency vibrational modes in a soft sphere
glass are extended to larger samples. We find a boson peak in the spectral density and a …

We work out a theory of low-energy Raman scattering in glasses. The scattering and the
energy transfer are due to interaction of the light with the soft potentials in glasses. We …