Related papers: Interplay of Rotational, Relaxational, and Shear D…
The frequency dependent specific heat has been measured under pressure for the molecular glass forming liquid 5-polyphenyl-4-ether in the viscous regime close to the glass transition. The temperature and pressure dependence of the…
Heat is carried in superfluid He-4 by the motion of the normal fluid$^{1}$, a counterflowing superfluid component serving to eliminate any net mass flow. It has been known for many years that above a critical heat current the superfluid…
Liquid foams are archetypal athermal amorphous solids whose elasticity arises from the jamming of densely packed bubbles. We investigate the stress relaxation of non-ageing liquid foams following flow cessation, using fast X-ray…
A novel density functional, which accounts correctly for the equation of state, the static response function and the phonon-roton dispersion in bulk liquid helium, is used to predict static and dynamic properties of helium droplets. The…
The shear stress relaxation modulus $G(t)$ may be determined from the shear stress $\tau(t)$ after switching on a tiny step strain $\gamma$ or by inverse Fourier transformation of the storage modulus $G^{\prime}(\omega)$ or the loss modulus…
We study the elastic properties of incommensurate solid 4He in the limit of zero temperature. Specifically, we calculate the pressure dependence of the five elastic constants (C11, C12, C13, C33, and C44), longitudinal and transversal…
The rotational property of a quantum liquid at the vicinity of the lambda point is examined. In a liquid helium 4 just above the lambda point, under the strong influence of Bose statistics, the coherent many-body wave function grows to an…
We present results of molecular dynamics simulations of the electron system on the surface of liquid helium. The simulations are done for 1600 electrons with periodic boundary conditions. Electron scattering by capillary waves and phonons…
The calculation of the He4 energy and specific heat is carried out in a wide temperature range within the two-time temperature Green functions approach. The approximation improving the random phase approximation is developed providing the…
Decoherent quantum equations of motion are derived that yield the trajectory of an open quantum system. The viscosity of superfluid Lennard-Jones helium-4 is obtained with a quantum stochastic molecular dynamics algorithm. The momentum…
Using molecular dynamics simulation, we calculate fluctuations and response for steadily sheared hard spheres over a wide range of packing fractions $\phi$ and shear strain rates $\gamma$, using two different methods to dissipate energy. To…
We have studied the fundamental rotational relaxation and excitation collision of OH- J=0 <-> 1 with helium at different collision energies. Using state-selected photodetachment in a cryogenic ion trap, the collisional excitation of the…
We construct a model of non-uniform condensate having a spatially modulated complex order parameter that makes it kinematically an x-ray solid, i.e., a real mass density wave, but one admitting an associated superfluid flow. Intrinsic to…
Using very long molecular dynamics simulation runs, temperature protocols spanning up to five orders of magnitude in time-scales are performed to investigate thermally activated structural relaxation in a model amorphous solid. The…
We present numerical results obtained from Time-Dependent Density Functional calculations of the dynamics of liquid He-4 in different environments characterized by geometrical confinement. The time-dependent density profile and velocity…
The torsional oscillator experiments described here examine the effect of disorder on the non-classical moment of inertia (NCRI) of a solid 4He sample. The NCRI increases with increasing disorder, but the period changes responsible for this…
We argue that the three key phenomena recently observed in solid $^4$He---mass supertransport, anomalous isochoric compressibility (syringe effect), and giant plasticity---are closely linked to each other through the physics of an…
Several experimental studies have reported thermally activated behavior of the mechanical response of solid Helium-4 which does not fit into the model of thermally activated Frenkel pairs in an ideal crystal. The purpose of the present work…
We investigate stresses and particle motion during the start up of flow in a colloidal dispersion close to arrest into a glassy state. A combination of molecular dynamics simulation, mode coupling theory and confocal microscopy experiment…
Oscillating solid bodies have frequently been used for studying the properties of normal and superfluid helium. In particular, the transition from laminar flow to turbulence has attracted much interest recently. The purpose of this note is…