Electronic Observables for Relaxed Bilayer 2D Heterostructures in Momentum Space
Electronic Observables for Relaxed Bilayer 2D Heterostructures in Momentum Space
复制标题
动量空间中松弛双层二维异质结构的电子可观测量
DOI：
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
M. Luskin
中科院分区：
文献类型：
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作者：
Daniel Massatt;S. Carr;M. Luskin
无公度二维电子结构计算的动量空间变换对于减少计算成本和以更具物理激励的形式表示数据是基本的，如Bstritzer-MacDonald模型所示。然而，这些转换可能很难在更复杂的系统中实现，例如当存在机械松弛模式时。在这项工作中，我们旨在实现两个目标。首先，我们努力简化这种变换的理解和实现，严格地写出四个相关空间之间的变换，我们表示实空间、构形空间、动量空间和倒易空间。这为从原始的实空间模型编写复动量空间模型提供了一种直接的算法。其次，我们对扭曲的双层石墨烯实现了这一点，并考虑了机械松弛效应。我们还分析了近似的收敛速度，结果表明，层与层之间的相对扭度越小，紧束缚耦合范围越大，说明当考虑很小角度的机械松弛时，Bistritzer-MacDonald模型的3近邻耦合是不够的。我们对此进行了量化，并进行了数值模拟验证。
Momentum space transformations for incommensurate 2D electronic structure calculations are fundamental for reducing computational cost and for representing the data in a more physically motivating format, as exemplified in the Bistritzer-MacDonald model. However, these transformations can be difficult to implement in more complex systems such as when mechanical relaxation patterns are present. In this work, we aim for two objectives. Firstly, we strive to simplify the understanding and implementation of this transformation by rigorously writing the transformations between the four relevant spaces, which we denote real space, configuration space, momentum space, and reciprocal space. This provides a straight-forward algorithm for writing the complex momentum space model from the original real space model. Secondly, we implement this for twisted bilayer graphene with mechanical relaxation affects included. We also analyze the convergence rates of the approximations, and show the tight-binding coupling range increases for smaller relative twists between layers, demonstrating that the 3-nearest neighbor coupling of the Bistritzer-MacDonald model is insufficient when mechanical relaxation is included for very small angles. We quantify this and verify with numerical simulation.
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影响因子：
4.2
作者：
Carr, Stephen;Massatt, Daniel;Kaxiras, Efthimios
通讯作者：
Kaxiras, Efthimios
影响因子：
1.3
作者：
Watson, Alexander B.;Luskin, Mitchell
通讯作者：
Luskin, Mitchell
影响因子：
41.2
作者：
Yoo, Hyobin;Engelke, Rebecca;Kim, Philip
通讯作者：
Kim, Philip
有效计算不相称二维异质结构的 Kubo 电导率
DOI：
10.1140/epjb/e2020-100518-7
发表时间：
2020
期刊：
The European Physical Journal B
影响因子：
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作者：
Massatt, Daniel;Carr, Stephen;Luskin, Mitchell
通讯作者：
Luskin, Mitchell