Related papers: Vortex excitation in superfluid 4He: A Diffusion M…
Monte Carlo simulations are performed to study the properties of type-II superconducting films in a magnetic field in which the vortices move in the two-dimensional geometry represented by the surface of a sphere. No numerical evidence is…
The behavior of quantum fluids (4He and H2) within nanopores is explored in various regimes, using several different methods. A focus is the evolution of each fluid's behavior as pore radius R is increased. Results are derived with the path…
We carry out driven diffusion Monte Carlo simulations of the two dimensional classical lattice Coulomb gas in an applied uniform electric field, as a model for vortex motion due to an applied d.c. current, in a periodic superconducting…
The motion of a vortex filament in superfluid 4He is considered by using the Hall-Vinen-Bekarevich-Khalatnikov (HVBK) phenomenological model for the scattering process between the vortex and thermal excitations in liquid 4He. The HVBK…
The experimental realization of a thin layer of spin-polarized hydrogen adsorbed on top of the surface of superfluid 4He provides one of the best examples of a stable nearly two-dimensional quantum Bose gas. We report a theoretical study of…
Excitations in the form of quantized vortex rings are known to exist in superfluid $^{4}He$ at energies and momenta exceeding those of the Landau phonon-roton spectrum. They form a vortex branch of elementary excitations spectrum which is…
The motion of a quantized vortex is intimately connected with its microscopic structure and the elementary excitations of the surrounding fluid. In this work, we investigate the two-dimensional motion of a single vortex orbiting a pinned…
Within Density Functional theory, we investigate stationary many-vortex structures in a rotating $^4$He nanocylinder at zero temperature. We compute the stability diagram and compare our results with the classical model of vortical lines in…
The superfluid transition of $^3$He-$^4$He mixture films adsorbed on alumina powder is studied, with a $^4$He superfluid coverage near one layer. With up to 1.3 layers of $^3$He added, the transition becomes strongly broadened, indicating a…
As is well-known, two-dimensional and three-dimensional superfluids under rotation can support topological excitations such as quantized point vortices and line vortices respectively. Recently, we have studied how, in a hypothetical…
We present a novel density functional for liquid 4He, properly accounting for the static response function and the phonon-roton dispersion in the uniform liquid. The functional is used to study both structural and dynamical properties of…
We revisited the phase diagram of the second layer of 4He on top of graphite using quantum Monte Carlo methods. Our aim was to explore the existence of the novel phases suggested recently in experimental works, and determine their…
Quantum vortices in superfluids have been an important research area for many decades. Naturally, research on this topic has focused on two and three-dimensional superfluids, in which vortex cores form points and lines, respectively. Very…
The spatial diffusion of an inhomogeneous vortex tangle is studied numerically with the vortex filament model. A localized initial tangle is prepared by applying a counterflow, and the tangle is allowed to diffuse freely after the…
The correlation energy of the homogeneous three-dimensional interacting electron gas is calculated using the variational and fixed-node diffusion Monte Carlo methods, with trial functions that include backflow and three-body correlations.…
By means of a Quadratic Diffusion Monte Carlo method we have performed a comparative analysis between the Aziz potential and a revised version of it. The results demonstrate that the new potential produces a better description of the…
Diagonal and off-diagonal properties of 2D solid 4He systems doped with a quantized vortex have been investigated via the Shadow Path Integral Ground State method using the fixed-phase approach. The chosen approximate phase induces the…
Vortex-loop renormalization is used to compute the specific heat of superfluid $^4$He near the lambda point at various pressures up to 26 bars. The input parameters are the the pressure dependence of T$_\lambda$ and the superfluid density,…
We report the observation of vortex formation upon the absorption of a thermal neutron in a rotating container of superfluid $^3$He-B. The nuclear reaction n + $^3$He = p + $^3$H + 0.76MeV heats a cigar shaped region of the superfluid into…
Using dynamic cluster quantum Monte Carlo simulations, we study the superconducting behavior of a 1/8 doped two-dimensional Hubbard model with imposed uni-directional stripe-like charge density wave modulation. We find a significant…