Related papers: Helium mixtures in nanotube bundles
We have discovered that the influence of the surrounding nanotubes in a bundle is similar to that of a liquid having surface tension equal to the surface energy of the nanotubes. This surprising behaviour is confirmed by the calculation of…
The adsorption phenomenon of neutral particles from the limiting surfaces of the sample in the Langmuir approximation is investigated. The diffusion equation regulating the redistribution of particles in the bulk is assumed to be of…
The diffusion of particles in confining walls forming a tube is discussed. Such a transport phenomenon is observed in biological cells and porous media. We consider the case in which the tube is winding with curvature and torsion, and the…
This paper presents an analysis of a model problem, consisting of two interacting rigid rings, for the rotation of molecules in liquid $^4$He. Due to Bose symmetry, the excitation of the rotor corresponding to a ring of N helium atoms is…
As helium-4 is cooled below 2.17 K it undergoes a phase transition to a fundamentally new state of matter known as a superfluid which supports flow without viscosity. This type of dissipationless transport can be observed by forcing helium…
Opposing the theory that Helium (He) cannot be inserted into AB-type ionic compounds due to the Madelung energy increase, our crystal structure search and first-principles calculations found that He can form stable compounds with sodium…
The properties of helium-filled nanopores in amorphous silicon are elucidated by combining theoretical knowledge of helium electronic structure with the results of Scanning Transmission electron microscopy/electron energy loss spectroscopy…
Equilibrium properties of hydrogen-helium mixtures under thermodynamic conditions found in the interior of giant gas planets are studied by means of density functional theory molecular dynamics simulations. Special emphasis is placed on the…
We study how adsorption of a near-critical binary mixture in a nanopore is modified by flow inside the pore. We identify three types of steady states upon variation of the pore P\'{e}clet number (${\rm Pe}_p$), which can be reversibly…
We theoretically study the stability of the solidified second-layer 3He at 4/7 of the first-layer density adsorbed on graphite, which exhibits quantum spin liquid. We construct a lattice model for the second-layer 3He by taking account of…
We have measured systematic repetitions of avoided crossings in low temperature three-terminal transport through a carbon nanotube with encapsulated C60 molecules. We show that this is a general effect of the hybridization of a host quantum…
We show that small amounts of 3He atoms, added to a 4He drop deposited on a flat cesium surface at zero temperature, populate bound states localized at the contact line. These edge states show up for drops large enough to develop well…
We perform a theoretical analysis of atomic four-wave mixing via a collision of two Bose-Einstein condensates of metastable helium atoms, and compare the results to a recent experiment. We calculate atom-atom pair correlations within the…
We investigate numerically the quantum collision between a stable Helium nanodrop and an infinitely hard wall in one dimension. The scattering outcome is compared to the same event omitting the quantum pressure. Only the quantum process…
The size effect in the gas of impuritons of the superfluid mixtures of helium isotopes is investigated by taking into consideration the contribution of thermal excitations. The solution is obtained for the set of kinetic equations…
Solid helium (3He and 4He) in the hcp and fcc phases has been studied by path-integral Monte Carlo. Simulations were carried out in the isothermal-isobaric (NPT) ensemble at pressures up to 52 GPa. This allows one to study the temperature…
We present static and dynamical properties of linear vortices in 4He droplets obtained from Density Functional calculations. By comparing the adsorption properties of different atomic impurities embedded in pure droplets and in droplets…
We have investigated cold ionizing heteronuclear collisions in dilute mixtures of metastable (2 3S1) 3He and 4He atoms, extending our previous work on the analogous homonuclear collisions [R. J. W. Stas et al., PRA 73, 032713 (2006)]. A…
We use molecular dynamics simulations to study the diffusion of water inside deformed carbon nanotubes with different degrees of deformation at 300 K. We found that the number of hydrogen bonds that water forms depends on nanotube topology,…
Experimental data suggests that, at temperatures below 1 K, the pressure in liquid helium has a cubic dependence on density. Thus the speed of sound scales as a cubic root of pressure. Near a critical pressure point, this speed approaches…