相关论文: On the possible "supersolid" character of parahydr…
We studied by means of computer simulations the low temperature properties of two-dimensional parahydrogen clusters comprising between 7 and 30 molecules. Computed energetics is in quantitative agreement with that reported in the only…
Structural and superfluid properties of para-Hydrogen clusters of size up to N=40 molecules, are studied at low temperature (0.5 K < T < 4 K) by Path Integral Monte Carlo simulations. The superfluid fraction displays an interesting,…
We study by Quantum Monte Carlo simulations the local superfluid response of small (up to 27 molecules) parahydrogen clusters, down to temperatures as low as 0.05 K. We show that at low temperature superfluidity is not confined at the…
The interplay between magic number stabilities and superfluidity of small para-hydrogen clusters with sizes $N = 5$ to 40 and temperatures $0.5 K \leq T \leq 4.5 $K is explored with classical and quantum Path Integral Monte Carlo…
We present results of computer simulations of a parahydrogen cluster of a thousand molecules, corresponding to approximately 4 nm in diameter, at temperatures between 1 K and 10 K. Examination of structural properties suggests that the…
We present results of a theoretical study of para-hydrogen and ortho-deuterium clusters at low temperature (0.5 K < T < 3.5 K), based on Path Integral Monte Carlo simulations. Clusters of size up to N=21 para-hydrogen molecules are nearly…
We study by computer simulations the effect of confinement on the superfluid properties of small two-dimensional (2D) parahydrogen clusters. For clusters of fewer than twenty molecules, the superfluid response in the low temperature limit…
It is shown by computer simulations that superfluid {\it para}-hydrogen clusters of more than 22 molecules can be turned insulating and "solidlike" by the replacement of as few as one or two molecules, with ones of the heavier {\it…
First principle computer simulations yield evidence of a finite superfluid response at low temperature of a parahydrogen cluster of 15 molecules in bulk superfluid He-4. The superfluid fraction is worth ~44% at T=0.25 K, growing to about…
We introduce a new criterion--based on multipole dynamical correlations calculated within Reptation Quantum Monte Carlo--to discriminate between a melting vs. freezing behavior in quantum clusters. This criterion is applied to small…
The possible superfluid transition of supercooled liquid parahydrogen is investigated by quantum Monte Carlo simulations. The cooling protocol adopted here allows for the investigation of a fluid phase down to a temperature T=0.25 K. No…
Computer simulations yield evidence of superfluid behavior of nanoscale size clusters of parahydrogen adsorbed on a graphite substrate at low temperature ($T\lesssim 0.25 \text{ K}$). Clusters with a number of molecules between 7 and 12…
We investigate mixed (50/50) clusters of parahydrogen and orthodeuterium at low temperature, by means of Quantum Monte Carlo simulations. Our results provide evidence of liquid-like behavior and partial isotopic separation in a cluster of…
Confinement can have a considerable effect on the behavior of particle systems, and is therefore an effective way to discover new phenomena. A notable example is a system of identical bosons at low temperature under an external field…
A recent claim of possible superfluid behaviour of parahydrogen films intercalated within a crystalline matrix of Na atoms is examined. Quantum Monte Carlo simulations at finite temperature yield strong numerical evidence that the system…
Molecular para-hydrogen has been proposed theoretically as a possible candidate for superfluidity, but the eventual superfluid transition is hindered by its crystallization. In this work, we study a metastable non crystalline phase of bulk…
Monodisperse ensembles of particles that have cluster crystalline phases at low temperatures can model a number of physical systems, such as vortices in type-1.5 superconductors, colloidal suspensions and cold atoms. In this work we study a…
The possibility that disorder may stabilize a superfluid phase of para-hydrogen in two dimensions is investigated theoretically by means of Quantum Monte Carlo simulations. We model disorder using a random distribution of scatterers, and…
We have determined the ground-state energies of para-H$_2$ clusters at zero temperature using the diffusion Monte Carlo method. The liquid or solid character of each cluster is investigated by restricting the phase through the use of proper…
We use molecular simulation to study the structural and dynamic properties of glassy nanoclusters formed both through the direct condensation of the vapor below the glass transition temperature, without the presence of a substrate, and…