Modern atomistic spin simulations combine long stochastic trajectories, thermodynamic sampling, static optimization and multi-image transition-path workflows, all of which rely on repeated evaluation of spin Hamiltonians and become computationally prohibitive on the large lattices required for three-dimensional magnetic textures. We introduce SpinX, a GPU-native atomistic spin simulation framework built around a unified Hamiltonian interface and multiple user-selectable computational backends. Its core is a crystallographic sublattice decomposition that reformulates translationally invariant spin interactions as multi-channel tensor convolutions, enabling dense, sparse and FFT-based convolution backends, while irregular systems are handled by pair-list evaluation and long-range dipolar fields by reciprocal-space FFT. Implemented in JAX, SpinX supports deterministic and stochastic Landau-Lifshitz-Gilbert dynamics, Monte Carlo sampling, static optimization, dynamical spectroscopy and string and geodesic nudged elastic band transition-path calculations on heterogeneous accelerator platforms. A validated mixed-precision mode combines fp32 field evaluation with fp64 spin-state propagation. We validate SpinX against analytical single-spin dynamics, finite-size thermodynamics of bcc Fe and transverse dynamic structure factors. Performance benchmarks show peak throughput exceeding 10 billion spin-site operations per second on a single accelerator and aggregate single-node workloads of over 1 billion atomic spins. Applying this framework to an exchange-stabilized magnetic hopfion, we uncover two competing annihilation channels on a million-spin atomistic lattice: a previously reported axial-collapse pathway and a distinct lateral-rupture pathway with a different transition morphology and activation barrier.(Due to arXiv's limit, the abstract shown here is a shortened version)

翻译：现代原子自旋模拟融合了长随机轨迹、热力学采样、静态优化及多图像过渡路径工作流，这些过程均依赖于自旋哈密顿量的重复计算，而在三维磁织构所需的大尺度晶格上计算成本极高。我们提出SpinX——基于GPU的原位原子自旋模拟框架，其核心为统一哈密顿接口与多用户可选计算后端。该框架采用晶体学子格分解技术，将平移不变自旋相互作用重构为多通道张量卷积，支持稠密、稀疏及基于FFT的卷积后端，不规则体系通过配对列表评估处理，长程偶极场则通过倒易空间FFT实现。基于JAX实现的SpinX支持确定性/随机朗道-利夫希茨-吉尔伯特动力学、蒙特卡洛采样、静态优化、动态谱学以及异构加速平台上的弦和测地线弹性带过渡路径计算。经验证的混合精度模式结合了fp32场评估与fp64自旋态传播。我们通过解析单自旋动力学、bcc铁有限尺寸热力学及横向动态结构因子对SpinX进行验证。性能基准测试表明，单加速器峰值吞吐量超每秒100亿自旋位点运算，单节点聚合工作负载超10亿原子自旋。将该框架应用于交换稳定磁霍普夫子，我们揭示了百万自旋原子晶格上两个竞争性湮灭通道：先前报道的轴向坍塌路径与具有不同转变形貌和活化能的横向断裂路径。（受arXiv篇幅限制，此处摘要为缩减版本）