Related papers: Many-body wavefunctions for normal liquid $^3$He
A numerical implementation scheme is presented for the recently developed many-body diffusion approach for identical particles, in the case of harmonic potentials. The procedure is free of the sign problem, by the introduction of the…
The attractive Fermi-Hubbard model stands out as a simple model for studying the pairing and superconductivity of fermions on a lattice. In this article, we apply several many-body theories in the three-dimensional attractive Hubbard model.…
We present a variational ansatz for the ground state of a strongly correlated Bose system. This ansatz goes beyond the Jastrow-Feenberg functional form and explicitly enforces coordination shells in the structure of the wavefunction. We…
We investigate the effect of three-body correlations on the phase behavior of hard rectangle two-dimensional fluids. The third virial coefficient, $B_3$, is incorporated via an equation of state that recovers scaled particle theory for…
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.…
A major challenge in modern physics is to accurately describe strongly interacting quantum many-body systems. One-dimensional systems provide fundamental insights since they are often amenable to exact methods. However, no exact solution is…
Some notable systems, such as room-temperature superconductors and materials for controlled nuclear fusion, require an accurate description of finite-temperature quantum matter. Stochastic path integral methods are finite-temperature and…
Among the many existing molecular models of water, the MB-pol many-body potential has emerged as a remarkably accurate model, capable of reproducing thermodynamic, structural, and dynamic properties across water's solid, liquid, and vapor…
We study the properties of three-body resonances using a lattice complex scalar $\varphi^4$ theory with two scalars, with parameters chosen such that one heavy particle can decay into three light ones. We determine the two- and three-body…
In a recent paper [Phys. Rev. A 99, 053617 (2019)], the total number of fermion pairs in a spin-balanced two-component Fermi gas of $^6$Li atoms was experimentally probed in the normal phase above the superfluid critical temperature, in…
We demonstrate that a conditional wavefunction theory enables a unified and efficient treatment of the equilibrium structure and nonadiabatic dynamics of correlated electron-ion systems. The conditional decomposition of the many-body…
In previous reports (arXiv:0901.2487, arXiv:1007.0745), we introduced a new fermionic variational wavefunction, suitable for interacting multi-species systems and sustaining superfluidity. This disentangled wavefunction contains a new…
In this article we calculate the energy of an impurity weakly coupled to a spin 1/2 fermionic superfluid. We show that the divergences resulting from three-body physics can only be cured using a proper description of the excitations of the…
We study the normal state of a 3-$d$ homogeneous dipolar Fermi gas beyond the Hartree-Fock approximation. The correlation energy is found of the same order as the Fock energy, unusually strong for a Fermi-liquid system. As a result, the…
This thesis presents a set of studies on atomic systems where quantum effects are particularly relevant. These studies have been developed by applying a variety of tools from many-body physics. First of all, we have studied the prospects…
We have investigated some of the thermodynamic properties of spin polarized liquid $^3\mathrm{He}$ at finite temperature using the lowest order constrained variational method. For this system, the free energy, entropy and pressure are…
We present the results of the computation of the third order corrections to the ground state energy of the diluted polarized gas of nonrelativistic spin $1/2$ fermions interacting through a spin-independent repulsive two-body potential. The…
An inhomogeneous backflow transformation for many-particle wave functions is presented and applied to electrons in atoms, molecules, and solids. We report variational and diffusion quantum Monte Carlo VMC and DMC energies for various…
We study three-body recombination of fully spin-polarized ${}^6$Li atoms that are interacting resonantly in relative p-waves. Motivated by a recent experiment, we focus on negative scattering volumes where three atoms recombine into a deep…
We generalize the methods used in the theory of correlation dynamics and establish a set of equations of motion for many-body correlation green's functions in the non-relativistic case. These non-linear and coupled equations of motion…