通过量子嵌入和空间截断加速单离子磁体的从头算自旋-声子弛豫模拟
Accelerating ab initio spin-phonon relaxation simulation of single-ion magnets by quantum embedding and spatial truncation
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University（北京大学化学与分子工程学院，北京分子科学国家实验室）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究将密度矩阵嵌入理论与空间截断结合，加速单离子磁体自旋-声子弛豫模拟，在保持精度下大幅降低计算成本，为高性能单分子磁体设计提供实用框架。
AI中文摘要：
单离子磁体（SIMs）在高密度存储和量子计算方面展现出应用前景，但由于需要大量非平衡多组态计算，预测自旋-声子耦合（SPC）和磁弛豫仍然具有挑战性。量子嵌入方法的最新进展为解决这一问题提供了潜在途径。在本工作中，将密度矩阵嵌入理论（DMET）与完全活性空间自洽场（CASSCF）方法相结合，对基于Dy$^{3+}$的单离子磁体的静态磁性质和自旋-声子耦合（SPC）参数进行了基准测试。该方法进一步与空间截断相结合，用于计算这些单离子磁体的SPC参数。研究发现，截断第一配位球附近的空间可大幅降低计算成本，同时使有效能垒和弛豫时间尺度的误差保持在可忽略的水平。本研究为准确高效的自旋动力学预测提供了一个实用的计算框架，为高性能单分子磁体的合理设计奠定了基础。
英文摘要：
Single-ion magnets (SIMs) show promise for high-density storage and quantum computing, but predicting spin-phonon coupling (SPC) and magnetic relaxation remains challenging due to the need for numerous non-equilibrium multiconfigurational calculations. Recent advances in quantum embedding methods offer a potential route to address this issue. In this work, density matrix embedding theory (DMET) combined with complete active space self-consistent field (CASSCF) is benchmarked for the static magnetic properties and spin-phonon coupling (SPC) parameters of Dy$^{3+}$-based SIMs. The method is further combined with spatial truncation to calculate SPC parameters for these SIMs. It is found that truncating the space near the first coordination sphere reduces the computational cost dramatically while keeping the errors in the effective energy barrier and relaxation time-scale negligible. This study provides a practical calculation framework for accurate and efficient spin dynamics prediction, laying the foundation for the rational design of high-performance single-molecule magnets.
