Hwave

H-wave

H-wave is a program for performing unrestricted Hartree-Fock (UHF) approximation and random phase approximation (RPA) for itinerant electron systems. UHF and RPA correspond to simple approximations that deal with fluctuations up to first order and enable analyses of electron correlation effects in materials at a low computational cost. The input files describing the one-body and two-body interactions are based on the Wannier90 format[1]. This allows smooth connection for the software packages that derive the effective models from first principles calculations, such as RESPACK[2], to the analyses of the effective model with H-wave.

[1] G. Pizzi et al, J. Phys.: Condens. Matter 32 165902 (2020).
[2] K. Nakmura, Y. Yoshimoto, Y. Nomura et al., Comp. Phys. Commun. 261, 107781 (2021).


Methods

Hartree-Fock and Random Phase approximation

Target models

Hubbard model, multi-orbital Hubbard model

Available physical quantities

ground-state energy, free energy, charge and spin susceptibilities, etc.

Requirement

Python3 with numpy, scipy, and other library packages

Install

- From PyPI

bash
python3 -m pip install hwave


- From source (if you modify the program)

bash
python3 -m pip install DIRECTORY_OF_THE_REPOSITORY


License

The distribution of the program package and the source codes for H-wave follow
GNU General Public License version 3
([GPL v3](https://www.gnu.org/licenses/gpl-3.0.en.html)).

Copyright (c) <2022-> The University of Tokyo. All rights reserved.

This software was developed with the support of
"Project for Advancement of Software Usability in Materials Science"
of The Institute for Solid State Physics, The University of Tokyo.

Official page

- [H-wave project site](https://www.pasums.issp.u-tokyo.ac.jp/h-wave/en)
- [Software repository](https://github.com/issp-center-dev/H-wave)
- [User Manual](https://www.pasums.issp.u-tokyo.ac.jp/h-wave/en/doc/manual)
- [Data Repository](https://datarepo.mdcl.issp.u-tokyo.ac.jp/repo/23)

Authors

Kazuyoshi Yoshimi (ISSP, Univ. of Tokyo),
Yuichi Motoyama (ISSP, Univ. of Tokyo),
Tatsumi Aoyama (ISSP, Univ. of Tokyo),
Kota Ido (ISSP, Univ. of Tokyo),
Takahiro Misawa (ISSP, Univ. of Tokyo),
Taiki Kawamura (Nagoya Univ.),
Akito Kobayashi (Nagoya Univ.),
Takeo Kato (ISSP, Univ. of Tokyo)

What's Changed
* The manual in English appears!
* The way to generate a random initial state is changed
* New option to switch Hartree/Hartree-Fock model for UHFk, `mode.flag_fock` is added.
* Data layout of eigenvalue and eigenvector output is corrected
* Samples are moved to an external repository
* https://isspns-gitlab.issp.u-tokyo.ac.jp/hwave-dev/hwave-gallery

H-wave

H-wave is a program for performing unrestricted Hartree-Fock (UHF) approximation
for itinerant electron systems.
The UHF method approximates two-body interaction terms into one-body ones by
taking account of the fluctuations up to the first order. The wave functions
and energies are determined self-consistently by an iterative method.
H-wave treats two types of UHF approximation: one is real-space and the other is
wavenumber-space UHF methods using translational symmetry. In the wavenumber space
UHF method, the input file defining the one-body and two-body interactions is
based on the Wannier90 format, and the program can be smoothly connected to
the softwares for deriving effective models from first-principles calculations.

Methods

Hartree-Fock approximation

Target models

Hubbard model, multi-orbital Hubbard model

Available physical quantities

ground-state energy, free energy, etc.

Requirement

Python3 with numpy, scipy, and other library packages

Install

- From PyPI

bash
python3 -m pip install hwave


- From source (if you modify the program)

bash
python3 -m pip install DIRECTORY_OF_THE_REPOSITORY


License

The distribution of the program package and the source codes for H-wave follow
GNU General Public License version 3
([GPL v3](https://www.gnu.org/licenses/gpl-3.0.en.html)).

Copyright (c) <2022-> The University of Tokyo. All rights reserved.

This software was developed with the support of
"Project for Advancement of Software Usability in Materials Science"
of The Institute for Solid State Physics, The University of Tokyo.

Official page

- [H-wave project site](https://www.pasums.issp.u-tokyo.ac.jp/h-wave/en)
- [Software repository](https://github.com/issp-center-dev/H-wave)
- [User Manual](https://www.pasums.issp.u-tokyo.ac.jp/h-wave/en/doc/manual)

Authors

Kazuyoshi Yoshimi,
Yuichi Motoyama,
Tatsumi Aoyama,
Kota Ido,
Takahiro Misawa,
Taiki Kawamura
Akito Kobayashi,
Takeo Kato