turboMagnon -- A code for the simulation of spin-wave spectra using the Liouville-Lanczos approach to time-dependent density-functional perturbation theory

TL;DR

turboMagnon is an open-source computational tool that uses advanced density-functional theory methods to accurately simulate magnetic excitations in solid materials, including complex spin interactions and spin-orbit effects.

Contribution

It introduces a novel implementation of the Liouville-Lanczos approach within a noncollinear, spin-orbit coupled framework for simulating spin-wave spectra.

Findings

Successfully computed magnon dispersions for CrI₃ monolayer.

Demonstrated the importance of spin-orbit coupling in magnetic excitations.

Optimized for high-performance parallel computing environments.

Abstract

We introduce turboMagnon, an implementation of the Liouville-Lanczos approach to linearized time-dependent density-functional theory, designed to simulate spin-wave spectra in solid-state materials. The code is based on the noncollinear spin-polarized framework and the self-consistent inclusion of spin-orbit coupling that allow to model complex magnetic excitations. The spin susceptibility matrix is computed using the Lanczos recursion algorithm that is implemented in two flavors - the non-Hermitian and the pseudo-Hermitian one. turboMagnon is open-source software distributed under the terms of the GPL as a component of Quantum ESPRESSO. As with other components, turboMagnon is optimized to run on massively parallel architectures using native mathematical libraries (LAPACK and FFTW) and a hierarchy of custom parallelization layers built on top of MPI. The effectiveness of the code is showcased by computing magnon dispersions for the CrI$_3$ monolayer, and the importance of the spin-orbit coupling is discussed.