Sunny is a Julia package designed to serve the needs of the quantum magnetism community. It supports the specification of a very broad class of spin models and a diverse suite of numerical solvers. These include powerful methods for simulating spin dynamics both in and out of equilibrium. Uniquely, it features a broad generalization of classical and semiclassical approaches to SU(N) coherent states, which is useful for studying systems exhibiting strong spin-orbit coupling or local entanglement effects. Sunny also offers a well-developed framework for calculating the dynamical spin structure factor, enabling direct comparison with scattering experiments. Ease of use is a priority, with tools for symmetry-guided modeling and interactive visualization.
@article{arxiv.2501.13095,
title = {Sunny.jl: A Julia Package for Spin Dynamics},
author = {David Dahlbom and Hao Zhang and Cole Miles and Sam Quinn and Alin Niraula and Bhushan Thipe and Matthew Wilson and Sakib Matin and Het Mankad and Steven Hahn and Daniel Pajerowski and Steve Johnston and Zhentao Wang and Harry Lane and Ying Wai Li and Xiaojian Bai and Martin Mourigal and Cristian D. Batista and Kipton Barros},
journal= {arXiv preprint arXiv:2501.13095},
year = {2025}
}