Organisers
- Claudia Filippi (Instituut Lorentz, Universiteit Leiden)
- William Matthew Colwyn Foulkes (Imperial College London)
- Richard Needs (Cavendish Laboratory, Cambridge)
Supports
CECAM
Psi-k
Description
The development of accurate quantum many-body methods for describing the correlated motion of electrons in matter is
a very important and active field. Quantum Monte Carlo (QMC)
is the most accurate method known for computing the energies of large assemblies of interacting quantum particles. QMC methods are also very flexible as any combination of fermion and boson particles can be treated with arbitrary external fields etc.
The cost of fermion QMC calculations normally scales with the cube of the number of particles, allowing applications to 100's or even 1000's of particles, which is enough to simulate condensed matter.
This workshop will deal with continuum wave-function based QMC
methods. The main focus will be on current methodological
developments in continuum QMC methods, including efforts to improve geometry optimisation schemes and incorporate molecular dynamics, to find more accurate parametrisations of many-body wave functions and better ways of optimising them, and to develop new algorithms as alternatives to the fixed-node diffusion Monte Carlo method. Work on pushing the frontier of applications to more complex systems and higher accuracy will also be presented. We wish to bring together QMC experts and new additions to the field. Therefore, we intend to involve a number of researchers from the quantum chemistry and density functional theory communities who have embraced quantum Monte Carlo approaches in recent years.
Scientific Objectives
The workshop will focus on advances in continuum quantum Monte Carlo (QMC) approaches, in particular recent methodological developments and applications to more complex systems. The current state of the art and prospects of these approaches will be reviewed and discussed, and outstanding issues such as the calculation of ionic forces, transition metals, the fermion sign problem, etc. will be covered.
We list below the main topics covered in the workshop:
- Calculation of energy derivatives and geometry optimisation within QMC.
- General and robust ways to obtain variational many-body wave functions.
- New and more accurate forms of many-body wave functions.
- New algorithms alternative to the fixed-node diffusion Monte Carlo method.
- Pseudopotentials in many-body calculations.
- Applications to more complex systems.
We also aim to bring together QMC experts and researchers entering the field, and to involve a larger community of electronic structure researchers with an interest in these techniques.
To encourage the participation of younger researchers, we plan to allocate a substantial amount of the budget to pay their travel expenses in addition to lodging.
Junior US researchers should apply for NSF travel support via the web
site http://www.mcc.uiuc.edu/travel/
Finally, the workshop is part of the activities of the quantum Monte Carlo working group WG2 of the ESF Psi-k Programme.
References
1) Quantum Monte Carlo Simulations of Solids, W.M.C. Foulkes, L. Mitas, R.J. Needs, and G. Rajagopal, Rev. Mod. Phys. 73, 33 (2001).
2) Equation of state and Raman frequency of diamond from quantum Monte Carlo simulations, Ryo Maezono, A. Ma, M.D. Towler, and R.J. Needs, Phys. Rev. Lett. 98, 025701 (2007).
3) Coupled Electron-Ion Monte Carlo Calculations of Dense Metallic Hydrogen, C. Pierleoni, D.M. Ceperley, and M. Holzmann, Phys. Rev. Lett. 93, 146402 (2004).
4) Efficient Quantum Monte Carlo Energies for Molecular Dynamics Simulations, J.C. Grossman and L. Mitas, Phys. Rev. Lett. 94, 056403 (2005).
5) Energy and Variance Optimization of Many-Body Wave Functions, C.J. Umrigar and C. Filippi, Phys. Rev. Lett. 94, 150201 (2005).
