Rimu.jl

Random Integrators for many-body quantum systems
Author joachimbrand
Popularity
5 Stars
Updated Last
2 Years Ago
Started In
June 2020

Rimu

Stable Dev

Random Integrators for many-body quantum systems

The grand aim is to develop a toolbox for many-body quantum systems that can be represented by a Hamiltonian in second quantisation language. Currently there are tools to find the ground state with FCIQMC or with a Lanczos algorithm (using KrylovKit for small Hilbert spaces). Later, we may add tools to solve the time-dependent Schrödinger equation and Master equations for open system time evolution.

Concept: Joachim Brand and Elke Pahl.

Contributors: Joachim Brand, Elke Pahl, Mingrui Yang, Matija Cufar.

Discussions, help, and additional contributions are acknowledged by Ali Alavi, Didier Adrien, Chris Scott (NeSI), Alexander Pletzer (NeSI).

Install Rimu

Rimu can be installed with the package manager directly from the github repository. Either hit the ] key at the Julia REPL to get into Pkg mode and type

pkg> add https://github.com/joachimbrand/Rimu.jl#master

where master can be exchanged with the name of the desired git branch. Alternatively, use

julia> using Pkg; Pkg.add(PackageSpec(url="https://github.com/joachimbrand/Rimu.jl", rev="master"))

Usage

The package is now installed and can be imported with

julia> using Rimu

Rimu offers a number of tools for representing Hamiltonians (see Hamiltonians) and state vectors / wave functions (see DictVectors) as well as algorithms to find the ground state, e.g. lomc!.

References:

The code implements the FCIQMC algorithm described in

  • "Fermion Monte Carlo without fixed nodes: A game of life, death, and annihilation in Slater determinant space", G. H. Booth, A. J. W. Thom, A. Alavi, J. Chem. Phys. 131, 054106 (2009).

Scientific papers using the Rimu code:

  • "Stochastic differential equation approach to understanding the population control bias in full configuration interaction quantum Monte Carlo", J. Brand, M. Yang, E. Pahl, arXiv:2103.07800 (2021).
  • "Improved walker population control for full configuration interaction quantum Monte Carlo", M. Yang, E. Pahl, J. Brand, J. Chem. Phys. 153, 170143 (2020); DOI: 10.1063/5.0023088; arXiv:2008.01927.

References: The code implements the FCIQMC algorithm described in

  • "Fermion Monte Carlo without fixed nodes: A game of life, death, and annihilation in Slater determinant space", G. H. Booth, A. J. W. Thom, A. Alavi, J. Chem. Phys. 131, 054106 (2009).

Scientific papers using the Rimu code:

For more information, consult the documentation.