转载自公众平台：npj计算材料学

现代自旋电子器件的发展离不开仿真模拟。由于计算量与模拟的分辨率紧密相关，我们往往会面临一个困境，即在较慢但准确的方法和较快但不精确的方法之间进行选择。

现有的微磁动态模拟软件（如OOMMF），在可接受的计算成本下，可以模拟大尺度、复杂结构的磁相互作用；另一边，VASP与QUANTUM ESPRESSO等软件则可以提供原子尺度上的精确计算。

但是介于两类之间的高精度、大尺度、高速度的微磁模拟依旧是一个空白。此外，在微磁领域里，磁隧道结等原型器件的模拟具有重要意义，将有助于自旋电子器件的设计，但这还处于空白。

来自波兰AGH理工大学电子研究院的Jakub Mojsiejuk等人，开发了一套开源的、计算效率高的标准化Python包—CMTJ程序，可用于多层自旋电子器件的快速原型化、大规模参数搜索和宏观自旋模拟。

例如，CMTJ能够模拟自旋转移矩理论框架下的电流诱导磁性动力学。此外，作者讨论了CMTJ的其他潜在应用与未来扩展方向。该软件包可为自旋器件的计算模拟提供强大的工具。相关论文近期发布于npj Computational Materials 9: 54 (2023)。

Editorial Summary

Modern development of spintronic devices requires the help of simulations. Because the computational cost is related to the atomic resolution in simulation, we are always facing the dilemma of choosing between a slower, but accurate approach and a faster, but not as precise method. Micromagnetic packages, such as OOMMF, can simulate magnetic interactions of large-scale and complex structures, while maintaining an acceptable computational cost; On the other side, such as VASP and QUANTUM ESPRESSO, will provide precise calculations at the atomic scale. 

However, a high-precision, large-scale and high-speed micromagnetic simulation package between these two types is still a blank. Besides, in the micromagnetic regime, the simulation of prototype devices such as magnetic tunnel junction is of great significance for the design of spintronic devices. 

Jakub Mojsiejuk et. al from Institute of Electronics, AGH University of Science and Technology, Poland, provided an open-source, computationally efficient standardized Python package, CMTJ, for rapid prototyping, large-scale parameter search, and macrospin simulation of multilayer systems. CMTJ is capable of simulating, for example, current-induced magnetization dynamics calculations originating from spin transfer torque. Meanwhile, the authors discussed the other underlying applications and future expansion directions of CMTJ. This software package provides a powerful tool for the simulations of spintronics. This article was recently published in npj Computational Materials 9: 54 (2023).

原文Abstract及其翻译

CMTJ: Simulation package for analysis of multilayer spintronic devices (CMTJ：用于多层自旋电子器件分析的仿真模拟软件包)

Jakub Mojsiejuk, Sławomir Ziętek, Krzysztof Grochot, Witold Skowroński & Tomasz Stobiecki 

Abstract We presentCMTJ—a simulation package for large-scale macrospin analysis of multilayer spintronics devices. Apart from conventional simulations, such as magnetoresistance and magnetisation hysteresis loops, CMTJ implements a mathematical model of dynamic experimental techniques commonly used for spintronics devices characterisation, for instance: spin diode ferromagnetic resonance, pulse-induced microwave magnetometry, or harmonic Hall voltage measurements. We find that macrospin simulations offer a satisfactory level of agreement, demonstrated by a variety of examples. As a unified simulation package, CMTJ aims to accelerate wide-range parameter search in the process of optimising spintronics devices.

摘要我们在此提供了一套仿真模拟软件包CMTJ，可用于多层自旋电子器件的大规模宏观自旋分析。除了传统的磁阻和磁滞回线等模拟，CMTJ还嵌入了一个数学模型，可用于模拟自旋电子学器件测量中用到的动态实验技术，例如：自旋二极管中的铁磁共振，脉冲诱导的微波磁学测量，或谐波霍尔电压测量。通过大量例证，我们认为宏观自旋模拟能够提供一个令人满意的模拟结果。作为一套统一的仿真模拟软件包，CMTJ旨在加速自旋电子学器件优化过程中的大范围参数搜索。

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