Pyqcm: An open-source Python library for quantum cluster methods

Abstract

Pyqcm is a Python/C++ library that implements a few quantum cluster methods with an exact diagonalization impurity solver. Quantum cluster methods are used in the study of strongly correlated electrons to provide an approximate solution to Hubbard-like models. The methods covered by this library are Cluster Perturbation Theory (CPT), the Variational Cluster Approach (VCA) and Cellular (or Cluster) Dynamical Mean Field Theory (CDMFT). The impurity solver (the technique used to compute the cluster's interacting Green function) is exact diagonalization from sparse matrices, using the Lanczos algorithm and variants thereof. The core library is written in C++ for performance, but the interface is in Python, for ease of use and inter-operability with the numerical Python ecosystem. The library is distributed under the GPL license.

revised submission to SciPost. Additional references added. New section on some issues with VCA, comments about respective merits of CPT, VCA and CDMFT. Various fixes and minor corrections added. arXiv admin note: substantial text overlap with arXiv:0806.2690

References in corpus (8)

• Variational cluster approach to correlated electron systems in low dimensions
• Variational cluster approach to spontaneous symmetry breaking: The itinerant antiferromagnet in two dimensions
• Self-energy-functional approach: Analytical results and the Mott-Hubbard transition
• Non-existence of the Luttinger-Ward functional and misleading convergence of skeleton diagrammatic series for Hubbard-like models
• First order Mott transition at zero temperature in two dimensions: Variational plaquette study
• Cellular Dynamical Mean Field Theory for the 1D Extended Hubbard Model
• Bath optimization in the Cellular Dynamical Mean Field Theory
• Pseudogap to metal transition in the anisotropic two-dimensional Hubbard model

Cited by in corpus (6)

• CDMFT+HFD : an extension of dynamical mean field theory for nonlocal interactions applied to the single band extended Hubbard model
• On the cuprates' universal waterfall feature: evidence of a momentum-driven crossover
• Next-generation EDIpack: A Lanczos-based package for quantum impurity models featuring general broken-symmetry phases, flexible bath topologies and multi-platform interoperability
• Bath parameterization in multi-band cluster Dynamical Mean-Field Theory
• Effect of the Coulomb repulsion and oxygen level on charge distribution and superconductivity in the Emery model for cuprates superconductors
• Cluster dynamical mean field study of intra-unit-cell charge nematicity in hole-doped cuprates