The purpose of this website is to provide links to useful scripts and packages contributed by users of the PythTB ("Python Tight Binding") program (see the About PythTB tab).
Listing of software on this site does not imply any sanction or approval on the part of the developers of PythTB. Users are responsible for testing and validation of the contributed software before using them in applications. Questions about individual packages should be addressed to the developers of the package in question.
Nicodemos Varnava and David Vanderbilt.
This extension package provides a routine for computing the partial Chern number for each orbital in a tight-binding model of a slab. This corresponds to the contribution of that orbital to the anomalous Hall conductivity (AHC) in the plane of the slab, and can be used to obtain a layer-by-layer decomposition of the AHC.
Available on GitHub HERE.
This extension enables the definition of TB models using the Slater-Koster (SK) parameterization. In this approximation, the hoppings between neighboring orbitals are expressed as functions of the distance between the orbitals, the direction cosines of the unit vector connecting them, and the chemical identity of the orbital pair (e.g., pp-σ, sp-σ, or pp-π). See J. C. Slater and G. F. Koster, Simplified LCAO method for the periodic potential problem, Phys. Rev. 94, 1498 (1954).
Available on GitHub HERE.
Mikel García and Iñigo Robredo.
This modification of PythTB implements the most performance-critical routines via just-in-time (JIT) compilation using Numba. In particular, the functions that solve the Hamiltonian are compiled to machine code and parallelized. This affects essential computations such as the calculation of bandstructures and Wannier charge centers. The speed gains are more noticeable in large tight-binding models, such as those obtained through the Wannier90 interface. For really simple models, the JIT-compilation overhead may not be worthwhile, since there is a one-time delay for the compilation.
The package is transparent to the user and succesfully runs all the examples for the original PythTB, so it is expected to work without issues.
Available on GitHub HERE.
Kuan-Sen Lin, Benjamin J. Wieder, and Barry Bradlyn.
This extension package provides two sets of routines for computing gauge-invariant nested Wilson loops (the non-Abelian Berry phases of hybrid Wannier sheets). First, the module nestedWilsonLib allows users to compute the nested Wilson loops of tight-binding models constructed in PythTB. Next, spin_resolved_analysis allows users to compute the spin-resolved bulk band structures, spin-resolved Wilson loops, and nested spin-resolved Wilson loops of spinful (nspin=2) tight-binding models constructed in PythTB. Documentation, several examples, and associated references are detailed in the readme.md file of the GitHub page linked below.
Available on GitHub HERE.