wannierberri 0.2.0

Advanced tool for Wannier interpolation

.:: . .::: :::. :::. :::.:::. :::. :::.,:::::: :::::::.. :::::::. .,:::::: :::::::.. :::::::.. ::: ';;, ;; ;;;' ;;;; ;;;;, ;;;;;;;, ;;; ;;;;;;;'''' ;;;;``;;;; ;;;'';;' ;;;;'''' ;;;;``;;;; ;;;;``;;;; ;;; '[[, [[, [[' ,[[ '[[, [[[[[. '[[ [[[[[. '[[ [[[ [[cccc [[[,/[[[' [[[__[[\. [[cccc [[[,/[[[' [[[,/[[[' [[[ Y$c$$$c$P c$$$cc$$$c $$$ "Y$c$$ $$$ "Y$c$$ $$$ $$"""" $$$$$$c $$""""Y$$ $$"""" $$$$$$c $$$$$$c $$$ "88"888 888 888, 888 Y88 888 Y88 888 888oo,__ 888b "88bo, _88o,,od8P 888oo,__ 888b "88bo, 888b "88bo,888 "M "M" YMM "" MMM YM MMM YM MMM """"YUMMM MMMM "W" ""YUMMMP" """"YUMMM MMMM "W" MMMM "W" MMM

a.k.a. Wannier19 __ ___
|_ (_ |_ _ _ _ _ | _ . _ | . _
|) / _) | (- |) (_| | ) | _) | | |( | | ) / | ```

I started this project by python realization of some of postw90 functional. Some parts of the code are an adapted translation of Wannier90 Fortran code: http://www.wannier.org/ https://github.com/wannier-developers/wannier90

The code is distributed under the terms of GNU GENERAL PUBLIC LICENSE Version 2, the same as Wannier90

At the moment the code calculates Anomalous Hall conductivity very fast (much faster then wannier90) with high precision over an ultradense k-grid. This is achieved due to :

1. Using Fast Fourier Transform
2. account of symmetries, to reduce integration to irreducible part of the Brillouin zone
3. recursive refinement algorithm
4. optimizing the implementation of scan of Fermi level and 'use_ws_distance' parameter (see wannier90 documentation for details)

Object oriented structure also makes it potentially easier to implement further features.

The usage of the code is demonstrated by "exampleFe" in the examples folder. AHC can also be calcualted for any tight-binding model, for which a "_tb.dat" file was generated in watever way.

WannierBerri can be run in parallel by means of multiprocessing module

instllation is possible by pip

pip3 install wannierberri

A simple exmple is contained in "tutorial/example.py" . That will produce AHC and tabulate the berry curvature and velocity of bcc iron more sofisticated features will be described soon.

The project started on June, 25th 2019. Any interest from the community will be motivating for developing.

Stepan Tsirkin, University of Zurich [e-mail]