Related papers: Quantum Monte Carlo simulation of overpressurized …
The roton in a Bose-Einstein condensate is computed, both near and far from a Feshbach resonance. A low-density approximation is made, allowing for an analytic result. A Monte Carlo calculation shows that the roton is larger than predicted…
Bose-Einstein condensation and the $\lambda$-transition are described in molecular detail for bosons interacting with a pair potential. New phenomena are identified that are absent in the usual ideal gas treatment. Monte Carlo simulations…
We perform molecular dynamics simulations driven by accurate Quantum Monte Carlo forces on dense liquid hydrogen. Recently it has been reported a complete atomization transition between a mixed-atomic liquid and a completely dissociated…
We perform path integral Monte Carlo simulations to study the imaginary time dynamics of metastable supercooled superfluid states and nearly superglassy states of a one component fluid of spinless bosons square wells. Our study shows that…
We study the superfluid density of hard-core bosons on quasi-one-dimensional lattices using the quantum Monte Carlo method. Because of phase slippage, the superfluid density drops quickly to zero at finite temperatures with increasing the…
The hybridization of the single-excitation branch with the two-excitation continuum in the momentum region beyond the roton minimum is reconsidered by including the effect of the interference term between one and two excitations. Fits to…
We present a new Monte Carlo method which couples Path Integral for finite temperature protons with Quantum Monte Carlo for ground state electrons, and we apply it to metallic hydrogen for pressures beyond molecular dissociation. This…
We develop a formalism to directly evaluate the matrix of force constants within a Quantum Monte Carlo calculation. We utilize the matrix of force constants to accurately relax the positions of atoms in molecules and determine their…
We present computer simulations of liquid and solid phases of condensed methane at pressures below 25 GPa, between 150 and 300 K, where no appreciable molecular dissociation occurs. We used molecular dynamics (MD) and metadynamics…
Monte Carlo simulations at constant pressure are performed to study coexistence and interfacial properties of the liquid-solid transition in hard spheres and in colloid-polymer mixtures. The latter system is described as a one-component…
We study the superfluid transition of $^4$He in aerogel by Monte Carlo simulations and finite size scaling analysis. Aerogel is a highly porous silica glass, which we model by a diffusion limited cluster aggregation model. The superfluid is…
A quantum Monte Carlo simulation of a system of hard rods in one dimension is presented and discussed. The calculation is exact since the analytical form of the wavefunction is known, and is in excellent agreement with predictions obtained…
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 ground state properties of spin-polarized deuterium (D$\downarrow$) at zero temperature are obtained by means of the diffusion Monte Carlo calculations within the fixed-node approximation. Three D$\downarrow$ species have been…
We study the zero-temperature equation of state (EOS) of solid 4He in the hexagonal closed packet (hcp) phase over the 0-57 GPa pressure range by means of the Diffusion Monte Carlo (DMC) method and the semi-empirical Aziz pair potential…
Employing a classical density-functional description of liquid environments, we introduce a rigorous method for the diffusion quantum Monte Carlo calculation of free energies and thermodynamic averages of solvated systems that requires…
Pressure-induced phase transitions of spin-crossover materials were simulated by a Monte Carlo simulation in the constant pressure ensemble for the first time. Here, as the origin of the cooperative interaction, we adopt elastic interaction…
Using an apparatus that allows superfluid liquid 4He to be in contact with hcp solid \4he at pressures greater than the bulk melting pressure of the solid, we have performed experiments that show evidence for 4He mass flux through the solid…
This article is a continuation of the past three papers, arXiv:1711.04976 (2017), arXiv:1809.04291 (2018), and arXiv:2006.09673v2 (2020), in which configurations of the molecules around a vacancy in solid CO2 with the Pa3 structure (phase…
We study thermal properties of a trapped Bose-Bose mixture in a dilute regime using quantum Monte Carlo methods. Our main aim is to investigate the dependence of the superfluid density and the condensate fraction on temperature, for the…