相关论文: Microscopic origin of Boson peak in amorphous soli…
Quantum droplets are ultradilute liquid states which emerge from the competitive interplay of two Hamiltonian terms, the mean-field energy and beyond-mean-field correction, in a weakly interacting binary Bose gas. We relate the formation of…
We show that the density of states of random wave equations, normalized by the square of the frequency, has a peak - sometimes narrow and sometimes broad - in the range of wave vectors between the disorder correlation length and the…
We demonstrate using the classical density functional theory (DFT) model that an intermediate degree of mass localization in the amorphous state is essential for producing the boson peak. The localization length $\ell$ is identified from…
Amorphous solids exhibit an excess of low-frequency vibrational modes beyond the Debye prediction, contributing to their anomalous mechanical and thermal properties. Although a $\omega^4$ power-law scaling is often proposed for the…
Many attempts to explain the Boson peak in the vibrational spectra of glasses consider models of a lattice of harmonic oscillators connected by spring constants of varying strength and randomly distributed. However, in real glasses one…
We investigate the vibrational density of states (vDOS) in harmonic approximation of a binary mixture of colloidal patchy particles with two and three patches for different relative compositions $x_2$. At low temperature, this system forms…
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 reduced density of low-frequency vibrational states g(w)/w^2. This…
A theory for the vibrational dynamics in disordered solids [W. Schirmacher, Europhys. Lett. {\bf 73}, 892 (2006)], based on the random spatial variation of the shear modulus, has been applied to determine the wavevector ($k$) dependence of…
The high-frequency excitations in glasses and supercooled liquids belong to the great mysteries of the physics of condensed matter. While the fast process, located at GHz-THz, can be interpreted as encaged molecular motion, the occurrence…
The active Brownian particle (ABP) model describes a swimmer, synthetic or living, whose direction of swimming is a Brownian motion. The swimming is due to a propulsion force, and the fluctuations are typically thermal in origin. We present…
In this study, a new alternative model algorithm has been proposed for assembling amorphous structures, unifying the bosonic paradigm applicable at low temperatures with crystalline models relevant at room and higher temperatures. Physical…
Glasses are amorphous solids, in the sense that they display elastic behaviour. In crystals, elasticity is associated with phonons, quantized sound-wave excitations. Phonon-like excitations exist also in glasses at very high frequencies…
We study the Boson Peak phenomenology experimentally observed in globular proteins by means of elastic network models. These models are suitable for an analytic treatment in the framework of Euclidean Random Matrix theory, whose predictions…
The phonon spectra of solids, described through the measurable vibrational density of states (VDOS), provide a wealth of information about the underlying atomic structure and bonding, and they determine fundamental macroscopic properties…
Glasses and disordered materials are known to display anomalous features in the density of states, in the specific heat and in thermal transport. Nevertheless, in recent years, the question whether these properties are really anomalous (and…
Despite the presence of topological disorder, phonons seem to exist also in glasses at very high frequencies (THz) and they remarkably persist into the supercooled liquid. A universal feature of such a systems is the Boson peak, an excess…
We introduce an algorithm that constructs disordered mass-spring networks whose elastic properties mimic that of glasses by tuning the fluctuations of the local elastic properties, keeping fixed connectivity and controlling the prestress.…
Contrary to previous studies of boson peak, we analyze the density of states and specific heat contribution of dispersion forces in an amorphous solid of nano-scales ($\sim 3 nm$). Our analysis indicates a universal semi-circle form of the…
A hallmark of glasses is an excess of low-frequency, nonphononic vibrations, in addition to phonons. It is associated with the intrinsically nonequilibrium and disordered nature of glasses, and is generically manifested as a THz peak -- the…
Vibrational density of states (VDOS) in a supercooled polydisperse liquid is computed by diagonalizing the Hessian matrix evaluated at the potential energy minima for systems with different values of polydispersity. An increase of…