The NanoTheory group at UC Davis is releasing κALDo: a new versatile and scalable opensource software to compute phonon transport in crystalline and amorphous solids.

 

κALDo features the real space Quasi-Harmonic Green-Kubo (QHGK) approach and three different solvers of the linearized Boltzmann Transport Equation (BTE): direct inversion, self-consistent, and relaxation time approximation.

The algorithms are implemented using linear algebra operations on tensors, to take advantage of multithreading on GPU and CPU using Numpy, Tensorflow and optimized tensor libraries.Using the Atomic Simulation Environment (ASE), κALDo can be interfaced to several ab initio, semiempirical and classical molecular dynamics codes to compute the interatomic  force constant. In addition, a native interface is available in the LAMMPS USER-PHONON package. Finally, through seamless integration with the hiPhive package, the IFC calculation can take advantage of compressed-sensing machine learning algorithms.

The code is released opensource for the community to use and contribute with edits and suggestions. It is designed on modern software best practices, and we hope to provide a development platform to implement new theory and methods.