Linear Spin Wave Theory
Overview
Open-source Python library for linear spin-wave theory (LSWT): defines spin systems on a lattice, builds and diagonalizes the LSWT Hamiltonian, and computes magnon spectra and their quantum corrections. Generalized out of the spin-wave component of the Spin Supersolid in Triangular Lattice project into a reusable package — still alpha and under validation ahead of a public release.
Design
- Separates system definition (
SpinSystem), solving (LSWTSolver,SpinOptimizer), results (SolverResult), observables, and visualization into independent layers. - Exchange-matrix support for Heisenberg, XXZ, spin-orbit coupling, Dzyaloshinskii-Moriya, and Kitaev interactions, alongside a dedicated NBCP (Na₂BaCo(PO₄)₂) exchange matrix.
- Keeps backward compatibility with the legacy dictionary-based input format from earlier in the project.
Status
SpinSystem,LSWTSolver,SpinOptimizer, andSolverResultare implemented, along with spin-arrangement visualization.- Thermodynamic, topological, and correlation-function observables exist as modules but aren’t yet wired into a high-level solver interface.
- Its main validation case reproduces LSWT results for Na₂BaCo(PO₄)₂, checked against Woodland et al., Physical Review B 112, 104413 (2025) and Gao et al., npj Quantum Materials 7, 89 (2022).