相关论文: High-frequency dynamics of type-B glass formers in…
Dielectric response as a function of frequency for high-permittivity dielectric and ferroelectric materials is discussed emphasizing the dynamic behaviour in the microwave and infrared range. After introducing the usual modelling of the…
We present time-dependent dielectric loss data at different frequencies for a variety of glass formers after cooling below the glass temperature. The observed aging dynamics is described using a modified Kohlrausch-Williams-Watts law, which…
Electrical conduction and relaxation phenomena in bismuth borate glasses in the composition 2Bi2O3-B2O3 (Bi4B2O9) were investigated. Dielectric studies carried out on these glasses revealed near constant loss (NCL) response in the 1 kHz to…
A new relaxation mechanism is shown to arise from overdamped two-level systems above a critical temperature $T^*\approx 5$ K, thus yielding an explanation for experimental observations in dielectric glasses in the temperature range between…
Multiferroic bismuth ferrite Bi_2Fe_4O_9 (BFO) ceramic was synthesized by conventional solid state reaction route. X-ray diffraction and Rietveld refinement show formation of single phase ceramic with orthorhombic crystal structure (space…
It was recently shown that different simple models of glass formers with binary interactions define a universality class in terms of the density of states of their quasi-localized low-frequency modes. Explicitly, once the hybridization with…
A simple model to investigate the long time dynamics of glass-formers is presented and applied to study a Lennard-Jones system in supercooled and glassy phases. According to our model, the point representing the system in the…
A relaxation process, with the associated phenomenology of sound attenuation and sound velocity dispersion, is found in a simulated harmonic Lennard-Jones glass. We propose to identify this process with the so called microscopic (or…
High frequency sound is observed in lithium diborate glass, Li$_2$O--2B$_2$O$_3$, using Brillouin scattering of light and x-rays. The sound attenuation exhibits a non-trivial dependence on the wavevector, with a remarkably rapid increase…
Silicene is becoming one of the most important two-dimensional materials. In this work, EEL Spectra were calculated for alfa-silicene (flat), and beta-silicene (low-buckled, and theoretically the most stable). Band structures were…
The glass transition of a hard sphere system is investigated within the framework of the density functional theory (DFT). Molecular dynamics (MD) simulations are performed to study dynamical behavior of the system on the one hand and to…
Soil as a complex multi-phase porous material typical exhibits several distributed relaxation processes in the frequency range from 1 MHz to approximately 10 GHz of interest in applications. To relate physico-chemical material parameters to…
We study the relation between short-time vibrational modes and long-time relaxational dynamics in a kinetically constrained lattice gas with harmonic interactions between neighbouring particles. We find a correlation between the location of…
There exists a variety of theories of the glass transition and many more numerical models. But because the models need built-in complexity to prevent crystallization, comparisons with theory can be difficult. We study the dynamics of a…
Employing wide-angle neutron spin echo spectroscopy, we measured the Q-dependent coherent intermediate scattering function of the prototypical ionic glass former Ca0.4K0.6(NO3)1.4, in the equilibrium and supercooled liquid states beyond the…
Relaxation of shear bands in a Pd40Ni40P20 bulk metallic glass was investigated by a combination of radiotracer diffusion and molecular dynamics (MD) simulations, allowing to determine for the first time the effective activation enthalpy of…
We numerically study dynamical properties of the one-component Gaussian Core Model in the supercooled states. We find that nucleation is suppressed as density increases. Concomitantly the system exhibits glassy slow dynamics characterized…
We investigate the relaxation process and the dynamical heterogeneities of the kinetically constrained Kob--Anderson lattice glass model, and show that these are characterized by different timescales. The dynamics is well described within…
The molecular mobility of glass and supercooled liquid states of nilutamide has been studied with broadband dielectric spectroscopy for a wide range of temperature and frequency. Besides primary $\alpha$-relaxation an excess wing like…
The emergence of nanoscience has increased the importance of experiments able to probe the very local structure of materials, especially for disordered and heterogeneous systems. This is technologically important; for example, the nanoscale…