相关论文: Unique dynamic crossover in supercooled x,3-dihydr…
We present extensive numerical investigations of the structural relaxation dynamics of a realistic model of the amorphous high-temperature ceramic a-Si$_3$B$_3$N$_7$, probing the mean square displacement (MSD) of the atoms, the bond…
The interrelation of dynamic processes active on separated time-scales in glasses and viscous liquids is investigated using a model displaying two time-scale bifurcations both between fast and secondary relaxation and between secondary and…
Supercooled liquids display dynamics that are inherently heterogeneous in space. This essentially means that at temperatures below the melting point, particle dynamics in certain regions of the liquid can be orders of magnitude faster than…
Using molecular dynamics simulations, we investigate the relation between the dynamic transitions of biomolecules (lysozyme and DNA) and the dynamic and thermodynamic properties of hydration water. We find that the dynamic transition of the…
Temperature-driven polyamorphism has been reported in various supercooled liquids and glasses. The dynamical and structural routes followed by the system during such crossovers are however not universal and appear to be related to intrinsic…
We present a novel mechanism for the anomalous behaviour of the specific heat in low-temperature amorphous solids. The analytic solution of a mean-field model belonging to the same universality class as high-dimensional glasses, the…
We present an extensive study of vortex dynamics in a high-quality single crystal of HgBa$_2$CuO$_{4+\delta}$ (Hg1201), a highly anisotropic superconductor that is a model system for studying the effects of anisotropy. From magnetization…
A central question concerning glass-formation has been what governs the kinetic arrest of the quenched liquid - cooling reduces the thermal energy which molecules need to surmount local potential barriers, while the accompanying volume…
A non-contact scanning-probe-microscopy method was used to probe local near-surface dielectric susceptibility and dielectric relaxation in poly-vinyl-acetate (PVAc) near the glass transition. Dielectric spectra were measured from 10-4 Hz to…
We give a simple demonstration of the formula relating the glass transition temperature, $T_g$, to the molar concentration $x$ of a modifier in two types of glasses: binary glasses, whose composition can be denoted by $X_nY_m+xM_pY_q$, with…
Strong changes in bulk properties, such as modulus and viscosity, are observed near the glass transition temperature, T_{g}, of amorphous materials. For more than a century, intense efforts have been made to define a microscopic origin for…
We have measured the linear dielectric susceptibility of two molecular glass formers close to Tg in order to estimate the size of the dynamically correlated clusters of molecules which are expected to govern the physics of glass formation.…
We study a schematic mode-coupling model in which the ideal glass transition is cut off by a decay of the quadratic coupling constant in the memory function. (Such a decay, on a time scale tau_I, has been suggested as the likely consequence…
A wide range of glassy and disordered materials exhibit complex, non-exponential, structural relaxation (aging). We propose a simple nonlinear rate equation d\delta/dt = a [1-exp (b\delta)], where '\delta' is the normalized deviation of a…
We show that in monomeric supercooled liquids and glasses that are plastically flowing at a constant shear stress $\sigma$ while being deformed with strain rate $\dot{\epsilon}$, the microscopic structural relaxation time $\tau_{\rm str}$…
We study the statistical mechanics and the equilibrium dynamics of a system of classical Heisenberg spins with frustrated interactions on a $d$-dimensional simple hypercubic lattice, in the limit of infinite dimensionality $d \to \infty$.…
We use recently introduced three-point dynamic susceptibilities to obtain an experimental determination of the temperature evolution of the number of molecules, N_corr, that are dynamically correlated during the structural relaxation of…
We show how dynamic heterogeneities (DH), a hallmark of glass-forming materials, depend on chain flexibility and chain length in polymers. For highly flexible polymers, a relatively large number of monomers ($N_c\sim500$) undergo correlated…
We have connected the dynamic fragility, namely the rapidity of the relaxation time increase upon temperature reduction, to the excess entropy and heat capacity of a large number of glass-forming polymers. The connection was obtained in a…
We find that a Lennard-Jones mixture displays a dynamic phase transition between an active regime and an inactive one. By means of molecular dynamics simulations and of a finite-size study, we show that the space time dynamics in the…