papers

Publications (15)

cond-mat.quant-gas2013

Phases of attractive spin-imbalanced fermions in square lattices

Simone Chiesa, Shiwei Zhang

We determine the relative stability of different ground-state phases of spin-imbalanced popula- tions of attractive fermions in square lattices. The phases are systematically chara…

cond-mat.quant-gas2014

FFLO order in ultra-cold atoms in three-dimensional optical lattices

Peter Rosenberg, Simone Chiesa, Shiwei Zhang

We investigate different ground-state phases of attractive spin-imbalanced populations of fermions in 3-dimensional optical lattices. Detailed numerical calculations are performed…

physics.comp-ph2005

Accurate, efficient and simple forces with Quantum Monte Carlo methods

Simone Chiesa, David Ceperley, Shiwei Zhang

Computation of ionic forces using quantum Monte Carlo methods has long been a challenge. We introduce a simple procedure, based on known properties of physical electronic densities…

physics.comp-ph2018

QMCPACK : An open source ab initio Quantum Monte Carlo package for the electronic structure of atoms, molecules, and solids

Jeongnim Kim, Andrew Baczewski, Todd D. Beaudet +45

QMCPACK is an open source quantum Monte Carlo package for ab-initio electronic structure calculations. It supports calculations of metallic and insulating solids, molecules, atoms,…

cond-mat.quant-gas2011

Magnetism and pairing of two-dimensional trapped fermions

Simone Chiesa, Christopher N. Varney, Marcos Rigol +1

The emergence of local phases in a trapped two-component Fermi gas in an optical lattice is studied using quantum Monte Carlo simulations. We treat temperatures that are comparable…

physics.chem-ph2001

Annihilation rate in positronic systems by quantum Monte Carlo. eLiH as test case

Massimo Mella, Simone Chiesa, Gabriele Morosi

An accurate method to compute the annihilation rate in positronic systems by means of quantum Monte Carlo simulations is tested and compared with previously proposed methods using…

cond-mat.str-el2013

Magnetic transition in a correlated band insulator

Axel Euverte, Simone Chiesa, Richard . T. Scalettar +1

The effect of on-site electron-electron repulsion in a band insulator is explored for a bilayer Hubbard Hamiltonian with opposite sign hopping in the two sheets. The ground sta…

physics.atom-ph2001

o-Positronium scattering off H and He

Simone Chiesa, Massimo Mella, Gabriele Morosi

Exploiting an approach similar to the R-matrix theory, the diffusion Monte Carlo method is employed to compute phase shifts and threshold cross sections for the elastic scattering…

cond-mat.quant-gas2011

The response to dynamical modulation of the optical lattice for fermions in the Hubbard model

Zhaoxin Xu, Simone Chiesa, Shuxiang Yang +5

Fermionic atoms in a periodic optical lattice provide a realization of the single-band Hubbard model. Using Quantum Monte Carlo simulations along with the Maximum Entropy Method, w…

cond-mat.str-el2013

Finite f-Electron Bandwidth in a Heavy Fermion Model

Axel Euverte, Simone Chiesa, Richard T. Scalettar +1

Determinant Quantum Monte Carlo (DQMC) is used to study the effect of non-zero hopping t_f in the localized f-band of the periodic Anderson model (PAM) in two dimensions. The low t…

cond-mat.other2006

The Finite Size Error in Many-body Simulations with long-Ranged Interactions

Simone Chiesa, David M. Ceperley, Richard M. Martin +1

We discuss the origin of the finite size error of the energy in many-body simulation of systems of charged particles and we propose a correction based on the random phase approxima…

cond-mat.quant-gas2016

Rashba spin-orbit coupling, strong interactions, and the BCS-BEC crossover in the ground state of the two-dimensional Fermi Gas

Hao Shi, Peter Rosenberg, Simone Chiesa +1

The recent experimental realization of spin-orbit coupled Fermi gases provides a unique opportunity to study the interplay between strong interaction and SOC in a tunable, disorder…

cond-mat.quant-gas2016

Exact Numerical Results on the Ground State of Strongly Interacting Fermi Gases in Two Dimensions

Hao Shi, Simone Chiesa, Shiwei Zhang

Exact calculations are performed on the two-dimensional strongly interacting, unpolarized, uniform Fermi gas with a zero-range attractive interaction. Two auxiliary-field approache…

cond-mat.str-el2013

Magnetic order in the repulsive Fermi-Hubbard model in three-dimensions and the crossover to two-dimensions

Jie Xu, Simone Chiesa, Eric J. Walter +1

Systems of fermions described by the three-dimensional (3D) repulsive Hubbard model on a cubic lattice have recently attracted considerable attention due to their possible experime…

cond-mat.str-el2008

Disorder-Induced Stabilization of the Pseudogap in Strongly Correlated Systems

Simone Chiesa, Prabuddha B. Chakraborty, Warren E. Pickett +1

The interplay of strong interaction and strong disorder, as contained in the Anderson-Hubbard model, is addressed using two non-perturbative numerical methods: the Lanczos algorith…