## Kwant extensions

Going beyond the core package, there are several tools that extend Kwant in useful ways. You can check these out below.

If you have some re-usable code that you think would be useful to the wider Kwant community, post to the Kwant development mailing list with a link to the code and a couple of sentences describing it, and we'll add it to this page.

## Semicon: k·p simulations made easy

**Get the code**: https://gitlab.kwant-project.org/semicon/semicon

A package of tools for doing k·p simulations. Contains: model definitions, material parameters, and helper functions for generating template Kwant systems.

## Generating quasicrystals

**Get the code**: https://arxiv.org/src/1510.06035v2/anc/quasicrystal.py

Code for reproducing numerics from the paper "Aperiodic Weak Topological Superconductors" by Fulga et al. Contains functionality for building 2D Ammann-Beenker tilings, an example of a quasicrystal, and Kwant systems constructed from such tilings.

## Time-dependent transport

**Get the code**: https://gitlab.kwant-project.org/jbweston/tkwant

A package for defining time-dependent systems with Kwant, and calculating time-dependent quantities. Details of the algorithm can be found in the following two papers:

## Qsymm: Symmetry finder and symmetric Hamiltonian generator

**Get the code**: https://gitlab.kwant-project.org/qt/qsymm

A package that makes symmetry analysis simple. It automatically generates model Hamiltonians from symmetry constraints and finds the full symmetry group of your Hamiltonian. Works with tight-binging and k dot p Hamiltonians and supports all kinds of symmetries, including conserved quantities, space group symmetries, time reversal, particle-hole and all combinations of these.