The udkm1Dsim toolbox is a collection of Python classes and routines to simulate the thermal, structural, and magnetic dynamics after laser excitation as well as the corresponding X-ray scattering response in one-dimensional samples, such as multilayers. The toolbox provides the capabilities to define arbitrary layered structures on the atomic level including a rich database of element-specific physical properties. The excitation of dynamics is represented by an N-temperature-model which is commonly applied in ultrafast physics. Structural dynamics due to thermal stresses are calculated by a linear-chain model of masses and springs. The implementation of specific magnetic dynamics can be easily accomplished by the user employing a generalized magnetization interface class. The resulting X-ray diffraction response is computed by kinematical or dynamical X-ray theory which can also include polarization-dependent magnetic scattering. The udkm1Dsim toolbox is highly modular and allows for injecting user-defined inputs at any step within the simulation procedure.

New version program summary

Program Title: udkm1Dsim

CPC Library link to program files: https://doi.org/10.17632/bnzw823v6y.1

Developer's repository link: https://github.com/dschick/udkm1Dsim

Code Ocean capsule: https://codeocean.com/capsule/8131941

Licensing provisions: MIT

Programming language: Python

Journal reference of previous version: Comput. Phys. Commun. 185 (2) (February 2014) 651–660

Does the new version supersede the previous version?: Yes

Reasons for the new version: The toolbox has been ported from MATLAB (MathWorks Inc.) to Python and is based exclusively on free and open-source components. Moreover, new features have been added that allow for a broader applicability of the toolbox.

Summary of revisions: Porting to Python.

Introduction of amorphous layers in the sample structures.

Add magnetization property to atoms and layers.

Multilayer formalism to calculate laser absorption.

New magnetization class to allow for user-defined magnetization dynamics.

New resonant magnetic X-ray scattering employing dynamical X-ray theory.

Calculation of X-ray scattering as function of photon energy and scattering vector.

Nature of problem: Simulate the thermal, structural, and magnetic dynamics of 1D layered sample structures due to an ultrafast laser excitation and compute the corresponding transient (magnetic) X-ray scattering response.

Solution method: The program provides an object-oriented toolbox for building arbitrary layered 1D crystalline/amorphous sample structures including a rich database of element-specific parameters. The excitation, thermal transport, and lattice dynamics are simulated utilizing SciPy's ODE solver. Magnetization dynamics can be introduced by the user employing a magnetization interface class. The dynamical (magnetic) X-ray scattering is computed by a matrix formalism that can be parallelized.

Additional comments including restrictions and unusual features: The program is restricted to 1D layered sample structures. Phonon dynamics only include longitudinal acoustic phonons (sound waves). Magnetization dynamics have to be defined by the user. X-ray scattering only allows for symmetrical and co-planar geometries due to the 1D nature of the toolbox. The program is highly modular and allows the inclusion of user-defined inputs at any time of the simulation procedure.

中文翻译：

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udkm1Dsim –一个Python工具箱，用于模拟凝聚态中的一维超快速动力学

所述udkm1Dsim工具箱是Python类和例程的集合来模拟激光激发以及一维样品，如多层在相应的X射线散射响应后的热，结构和磁动力学。该工具箱提供了在原子级别上定义任意分层结构的功能，其中包括丰富的元素特定物理特性数据库。动力的激发由N表示温度模型，通常用于超快物理学中。通过质量和弹簧的线性链模型计算由于热应力引起的结构动力学。用户可以使用广义的磁化接口类别轻松地实现特定磁动力学的实现。所得的X射线衍射响应是通过运动X射线理论或动态X射线理论计算得出的，该理论也可以包括偏振相关的磁散射。所述udkm1Dsim工具箱高度模块化，允许在模拟过程中的任何步骤注入的用户定义输入。

新版本程序摘要

程式名称： udkm1Dsim

CPC库链接到程序文件： https : //doi.org/10.17632/bnzw823v6y.1

开发人员的资料库链接： https : //github.com/dschick/udkm1Dsim

Code Ocean太空舱： https : //codeocean.com/capsule/8131941

许可条款：麻省理工学院

编程语言： Python

先前版本的期刊参考：计算。物理 公社 185（2）（2014年2月）651–660

新版本会取代旧版本吗？：是

使用新版本的原因：该工具箱已从MATLAB（MathWorks Inc.）移植到Python，并且完全基于免费和开源组件。此外，添加了新功能，可以使工具箱具有更广泛的适用性。

修订摘要：移植到Python。

在样品结构中引入非晶层。

为原子和层添加磁化特性。

多层形式来计算激光吸收。

新的磁化等级，允许用户定义磁化动力学。

运用动态X射线理论的新型共振磁X射线散射。

X射线散射与光子能量和散射矢量的函数关系。

问题性质：由于超快激光激发，模拟一维分层样品结构的热，结构和磁动力学，并计算相应的瞬态（磁性）X射线散射响应。

解决方法：该程序提供了一个面向对象的工具箱，用于构建任意分层的一维晶体/非晶样品结构，包括丰富的元素特定参数数据库。利用SciPy的ODE求解器模拟了激发，热传输和晶格动力学。用户可以使用磁化接口类来引入磁化动力学。动态（磁性）X射线散射是通过可以并行化的矩阵形式来计算的。

其他注释包括限制和异常功能：该程序仅限于一维分层的样本结构。声子动力学仅包括纵向声子（声波）。磁化动力学必须由用户定义。由于工具箱的一维特性，X射线散射仅允许对称和共面的几何形状。该程序是高度模块化的，并允许在仿真过​​程中的任何时候包含用户定义的输入。