KeldyshED

The package KeldyshED.jl is a small scale Equilibrium Exact Diagonalization solver for finite fermionic models. It can compute single-particle Green's functions in the (Matsubara) imaginary time domain, on the 2-branch Keldysh contour, and on the 3-branch Konstantinov-Perel' contour.

Its main intended use is solution of auxiliary problems required by more advanced solvers such as the Hybridization Expansion Quantum Monte Carlo and the N-crossing approximations.

The initial public version of this package was a simplified Julia port of the TRIQS/atom_diag library, but has since acquired a number of unique features, e.g. calculation of Evolution operators.

Installation

KeldyshED.jl is a registered Julia package that can be installed via the following invocation

using Pkg
Pkg.add("KeldyshED")

Public API

• Expressions with creation/annihilation operators of fermions
• • Canonical operators
  • Monomials
  • Polynomial expressions
  • Factory functions for polynomial expressions
• Hilbert spaces, states and linear operators
• • Ordered set of compound indices
  • Full Hilbert spaces and their subspaces
  • Quantum states
  • Operators acting in Hilbert spaces
  • Space autopartition algorithm
• Exact Diagonalization solver
• • Core ED types and functions
  • Utility functions
• Single-particle Green's functions
• • computegf()
  • Auxiliary types
• Density matrix and evolution operators

License

KeldyshED.jl is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

KeldyshED.jl is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with KeldyshED.jl (in the file LICENSE in this directory). If not, see http://www.gnu.org/licenses/.