相关论文: Sound Velocity in Liquid and Glassy Selenium
Glasses display a wide array of nonlinear acoustic phenomena at temperatures $T\lesssim 1$ K. This behavior has traditionally been explained by an ensemble of weakly-coupled, two-level tunneling states, a theory that is also used to…
The persistent problem posed by the glass transition is to develop a general atomic level description of a solidification process that is not associated with any change in the symmetry of the atomic structure. The answer proposed in this…
We compute the thermal conductivity and sound attenuation length of a dilute atomic Fermi gas in the framework of kinetic theory. Above the critical temperature for superfluidity, T_c, the quasi-particles are fermions, whereas below T_c,…
Temperature rise ($\Delta T$) associated with shear-banding of metallic glasses is of great importance for their performance. However, experimental measurement of $\Delta T$ is difficult due to temporal and spatial localization of shear…
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…
We calculate the speed of sound $c_s$ in an ideal gas of resonances whose mass spectrum is assumed to have the Hagedorn form $\rho(m) \sim m^{-a}\exp{bm}$, which leads to singular behavior at the critical temperature $T_c = 1/b$. With $a =…
The glass transition temperature and its connection to statistical properties of confined and free-standing polymer films of varying thickness containing unentangled to highly entangled bead-spring chains are studied by molecular dynamics…
Using a realistic flexible molecule model of the fragile glass former orthoterphenyl, we calculate via molecular dynamics simulation the collective dynamic structure factor, recently measured in this system by Inelastic X-ray Scattering.…
It has been established that the low frequency quasi-localized modes of amorphous solids at zero temperature exhibit universal density of states, depending on the frequencies as $D(\omega) \sim \omega^4$. It remains an open question whether…
High-resolution, inelastic x-ray scattering measurements of the dynamic structure factor S(Q,\omega) of liquid water have been performed for wave vectors Q between 4 and 30 nm^-1 in distinctly different thermodynamic conditions (T= 263 -…
While deeply supercooled liquids exhibit divergent viscosity and increasingly heterogeneous dynamics as the temperature drops, their structure shows only seemingly marginal changes. Understanding the nature of relaxation processes in this…
The manipulation of sound with acoustic metamaterials is a field of intense research, where interaction via resonance is a common application despite the significant disadvantages. We propose a novel procedure for introducing well-designed…
The flow velocity of solid 4He through a porous membrane frozen into a crystal has been measured in the temperature interval 0.1 - 1.8 K. A flat capacitor consisting of a metalized plastic porous membrane and a bulk electrode is applied and…
We study amorphous solids with strong elastic disorder and find an un-jamming instability that exists, inter alia, in an harmonic model built using Euclidean random matrices (ERM). Employing the Zwanzig-Mori projection operator formalism…
The molecular mobility of glassy and supercooled liquid states of clotrimazole is studied using broadband dielectric spectroscopy for a wide range of temperatures and frequency. The dielectric loss data of clotrimazole below T$_{g}$, do not…
The existence of a static lengthscale that grows in accordance with the dramatic slowing down observed at the glass transition is a subject of intense interest. A recent publication compared two proposals for this length scale, one based on…
Superfluidity, liquid flow without friction, is familiar in helium. The first evidence for "supersolidity", its analogue in quantum solids, came from recent torsional oscillator (TO) measurements involving 4-He. At temperatures below 200…
We develop a transferable machine learning model which predicts structural relaxation from amorphous supercooled liquid structures. The trained networks are able to predict dynamic heterogeneity across a broad range of temperatures and time…
We performed parallel measurements of the high-frequency shear modulus $G$ and relative volume $\Delta V/V$ for high-entropy Ti$_{20}$Zr$_{20}$Hf$_{20}$Be$_{20}$Cu$_{20}$ and Ti$_{20}$Zr$_{20}$Hf$_{20}$Be$_{20}$Ni$_{20}$ glasses upon…
Recently interest in calculations of the speed of sound in QCD under conditions like constant temperature $c^2_T$ or constant entropy per net baryon number $c^2_s$ arose in the discussion of experimental results coming from heavy ion…