jbweston / kwant_tools

A small set of utilities for working with the Kwant library for quantum transport simulations.

Kwant Tools

A small set of utilities for use with the Kwant package for quantum transport simulations.

Kwant is a very general and powerful library. Part of its design philosophy is to keep it reasonably lean so as not to burden the user with a load of functionality that they don't need. In this way it is a framework in which to implement quantum transport simulations, rather than a plug-and-play simulation package. The downside of this design philosophy is that there are often common idioms that have to be implemented and re-implemented by the users themselves, because the concepts are not sufficiently general to be included in Kwant.

kwant_tools is a set of utilities that I have personally found useful for working with Kwant, as such it is in no way meant to be "complete". That being said, anyone who finds it useful is free to use it under the MIT licence, the conditions of which are stated in the LICENSE file. The wraparound module was written by Christoph Groth, and is under the Kwant 2-clause BSD license

Contents

• lattice.py: utilities for working with Kwant lattices. Includes functions for connecting sites in a system from arbitrary lattices subject to some criterion, and some functionality for more easily working with symmetries.

• spin.py: utilities for working with spin as an internal degree of freedom (i.e. matrix onsite/hoppings, as opposed to separate lattices).

• wraparound.py: a utility to modify a Builder to allow for 2D band structures to be calculated.

Contributing

I'd be happy to accept pull/merge requests if anyone else has any tools they'd like to add to this collection.