Related papers: Absence of off-diagonal long-range order in hcp $^…
We contend that the arguments provided in Phys. Rev. Lett. 130, 016001 (2023), purporting to show the absence of off-diagonal long-range order in hcp $^4$He dislocation cores are misleading and incorrect. In particular, the one-body density…
Defects are believed to play a fundamental role in the supersolid state of 4He. We report on studies by exact Quantum Monte Carlo (QMC) simulations at zero temperature of the properties of solid 4He in presence of many vacancies, up to 30…
We investigate the structure and mobility of dislocations in hcp 4He crystals. In addition to fully characterizing the five elastic constants of this system, we obtain direct insight into dislocation core structures on the basal plane,…
The ground state of solid $^4$He is studied using the diffusion Monte Carlo method and a new trial wave function able to describe the supersolid. The new wave function is symmetric under the exchange of particles and reproduces the…
We have investigated the ground state properties of solid $^4$He with the Shadow Path Integral Ground State method. This exact T=0 K projector method allows to describes quantum solids without introducing any a priori equilibrium position.…
Measurements of the moment of inertia by Kim and Chan have found that solid 4He acts like a supersolid at low temperatures. To understand the order in solid 4He, we have used Path Integral Monte Carlo to calculate the off-diagonal long…
The paper presents a study of two full-core, edge dislocations of opposite Burgers vectors in 4H-SiC, conducted using the first-principles density functional theory methods. We have determined the creation energy of the dislocations as a…
In the experiment on superfluid transport in solid He4 [PRL {\bf 100}, 235301 (2008)], Ray and Hallock observed an {\it anomalously large isochoric compressibility}: the supersolid samples demonstrated a significant and apparently spatially…
Motivated by recent experiments on the supersolid behavior of $^4$He, we study the effect of an edge dislocation in promoting superfluidity in a Bose crystal. Using Landau theory, we couple the elastic strain field of the dislocation to the…
We have computed the one--body density matrix rho_1 in solid 4He at T=0 K using the Shadow Wave Function (SWF) variational technique. The accuracy of the SWF has been tested with an exact projector method. We find that off-diagonal long…
Defects are believed to play a fundamental role in the supersolid state of 4He. We have studied solid 4He in two dimensions (2D) as function of the number of vacancies n_v, up to 30, inserted in the initial configuration at rho = 0.0765…
We have studied a two-dimensional triangular commensurate crystal of 4He with the exact T=0 K Path Integral Ground State (PIGS) Monte Carlo method. We have projected onto the true ground state both a Jastrow-Nosanow wave function, in which…
In this work we investigate the quantum nature of bcc $^{4}$He. We show that it is a solid phase with an Off-Diagonal Long Range Order of coherently oscillating local electric dipole moments. These dipoles arise from the correlated…
A translational gauge approach of the Einstein type is proposed for obtaining the stresses that are due to non-singular screw dislocation. The stress distribution of second order around the screw dislocation is classically known for the…
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…
Topological materials occupy the central stage in the modern condensed matter physics because of their robust metallic edge or surface states protected by the topological invariant, characterizing the electronic band structure in the bulk.…
Dislocation core properties of tin (\beta-Sn) were investigated using the semi-discrete variational Peierls-Nabarro model (SVPN). The SVPN model, which connects the continuum elasticity treatment of the long-range strain field around a…
Ti exhibits complex plastic deformation controlled by active dislocation and twinning systems. Understandings on dislocation cores and twin interfaces are currently not complete or quantitative, despite extensive experimental and simulation…
We elucidated the core structure of screw dislocations in ordered B2 FeCo using a recent magnetic bond-order potential (BOP) [Egorov et al., Phys. Rev. Mater. 7, 044403 (2023)]. We corroborated that dislocations in B2 FeCo exist in pairs…
On the basis of first-principle Monte Carlo simulations we find that the screw dislocation along the hexagonal axis of an hcp He4 crystal features a superfluid core. This is the first example of a regular quasi-one-dimensional supersolid,…