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DOE OSTI · 3010640

Sunny.jl: A Julia Package for Spin Dynamics

Dahlbom, David [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000202215086)·Zhang, Hao [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000297999118)·Miles, Cole [Kodiak Robotics, Mountain View, CA (United States)] (ORCID:0000000255814226)·Quinn, Sam [Georgia Institute of Technology, Atlanta, GA (United States); Univ. of California, Los Angeles, CA (United States)] (ORCID:0000000250433934)·Niraula, Alin [Louisiana State Univ., Baton Rouge, LA (United States)] (ORCID:0009000241390140)·Thipe, Bhushan [Louisiana State Univ., Baton Rouge, LA (United States)] (ORCID:0009000133190627)·Wilson, Matthew [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000322983477)·Matin, Sakib [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000151662838)·Mankad, Het [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000034339599X)·Hahn, Steven [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000220187904)·Pajerowski, Daniel M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000338902379)·Johnston, Steve [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000223430113)·Wang, Zhentao [Zhejiang Univ., Hangzhou (China)] (ORCID:0000000174422933)·Lane, Harry [Univ. of Manchester (United Kingdom); Univ. of Manchester, Harwell (United Kingdom); Univ. of St. Andrews, Scotland (United Kingdom)] (ORCID:0009000503914750)·Li, Ying Wai [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000301248262)·Bai, Xiaojian [Louisiana State Univ., Baton Rouge, LA (United States)] (ORCID:000000023974626X)·Mourigal, Martin [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000327728440)·Batista, Cristian D. [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000316673667)·Barros, Kipton [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000213335972)
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Abstract

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.

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97 MATHEMATICS AND COMPUTING

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Dahlbom, David [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000202215086), Zhang, Hao [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000297999118), Miles, Cole [Kodiak Robotics, Mountain View, CA (United States)] (ORCID:0000000255814226), Quinn, Sam [Georgia Institute of Technology, Atlanta, GA (United States); Univ. of California, Los Angeles, CA (United States)] (ORCID:0000000250433934), Niraula, Alin [Louisiana State Univ., Baton Rouge, LA (United States)] (ORCID:0009000241390140), Thipe, Bhushan [Louisiana State Univ., Baton Rouge, LA (United States)] (ORCID:0009000133190627), Wilson, Matthew [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000322983477), Matin, Sakib [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000151662838), Mankad, Het [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000034339599X), Hahn, Steven [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000220187904), Pajerowski, Daniel M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000338902379), Johnston, Steve [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000223430113), Wang, Zhentao [Zhejiang Univ., Hangzhou (China)] (ORCID:0000000174422933), Lane, Harry [Univ. of Manchester (United Kingdom); Univ. of Manchester, Harwell (United Kingdom); Univ. of St. Andrews, Scotland (United Kingdom)] (ORCID:0009000503914750), Li, Ying Wai [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000301248262), Bai, Xiaojian [Louisiana State Univ., Baton Rouge, LA (United States)] (ORCID:000000023974626X), Mourigal, Martin [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000327728440), Batista, Cristian D. [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000316673667), Barros, Kipton [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000213335972). 2025-12-20. Sunny.jl: A Julia Package for Spin Dynamics. https://doi.org/10.21105/joss.08138

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