相关论文: Emergence of structural anisotropy in Optical Glas…
We explore, by means of inelastic neutron scattering, the extent of changes in dynamic correlations induced by thermal poling of vitreous $SiO_2$. The measured vibrational density of states shows an excess of modes in certain frequency…
Experimentally resolving atomic-scale structural changes of a deformed glass remains challenging owing to the disordered nature of glass structure. Here, we show that the structural anisotropy emerges as a general hallmark for different…
Any material in thermal equilibrium exhibits fundamental thermodynamic fluctuations of its mechanical and optical properties. Such thermodynamic fluctuations of length, elastic constants, and refractive index of amorphous materials -- like…
Influence of material anisotropy and gyrotropy on optical properties of fractal multilayer nanostructures is theoretically investigated. Gyrotropy is found to uniformly rotate the output polarization for bi-isotropic multilayers of…
Structural, vibrational and thermal properties of densified sodium silicate (NS2) are investigated with classical molecular dynamics simulations of the glass and the liquid state. A systematic investigation of the glass structure with…
Using a modified Lennard-Jones model for anisotropic particles, we present results of molecular dynamics simulation in two dimensions. In one-component systems, we find crystallization, a Berezinskii-Kosterlitz-Thouless phase, and a…
Ordering of disordered materials occurs during the activated process of nucleation that requires the formation of critical clusters that have to surmount a thermodynamic barrier. The characterization of these clusters is experimentally…
Femtosecond laser exposure in the non-ablative regime induces a variety of bulk structural modifications, in which anisotropy may depend on the polarization of the writing beam. In this work, we investigate the correlation between…
We present a study of orientational relaxation dynamics in thin films of a low-molecular-weight glass-former as a function of temperature and film thickness. The relaxation is probed by second-harmonic generation after release of a poling…
It is a persistent problem in condensed matter physics that glasses exhibit vibrational and thermal properties that are markedly different from those of crystals. While recent works have advanced our understanding of vibrational excitations…
Studies of low-frequency resistance noise demonstrate that glassy freezing occurs in a two-dimensional electron system in silicon in the vicinity of the metal-insulator transition (MIT). The width of the metallic glass phase, which…
The NaNO$_{2}$ nanocomposite ferroelectric material in porous glass was studied by neutron diffraction. For the first time the details of the crystal structure including positions and anisotropic thermal parameters were determined for the…
Understanding and controlling physical aging, i.e. the spontaneous temporal evolution of out-of-equilibrium systems, represents one of the greatest tasks in material science. Recent studies have revealed the existence of a complex atomic…
The evolution of porous structure and mechanical properties of binary glasses under tensile loading were examined using molecular dynamics simulations. We consider vitreous systems obtained in the process of phase separation after a rapid…
Tuning anisotropy in bulk metallic glasses, ideally isotropic, is of practical interest in optimizing properties and of fundamental interest in understanding the amorphous structure and its instability. By employing the quasi-elastic…
By considering Voronoi tessellations of the configurations of a fluid, we propose two new conserved fields, which provide structural information not fully accounted for by the usual 2-point density field fluctuations (structure factor). One…
The atomistic mechanisms occurring during the processes of aging and rejuvenation in glassy materials involve very small structural rearrangements that are extremely difficult to capture experimentally. Here we use in-situ X-ray diffraction…
We use molecular dynamics simulations and the Voronoi tessellation to study the geometrical modifications as a function of temperature in a model silica glass. The standard deviation of the cell volumes, which is a measure of the local…
The effects of plasticization of poly(methyl methacrylate) glass on the boson peaks observed by Raman and neutron scattering are compared. In plasticized glass the cohesion heterogeneities are responsible for the neutron boson peak and…
In this work, nonlinear optical (NLO) studies of nickel oxide doped (ranging from 0.2 to 1.0 mol%) Li2SO4-MgO-P2O5 glasses are reported. A combination of femtosecond (fs) laser, as a pumping light source and a high-accuracy polarimeter with…