论文标题
从4D STEM数据中深入学习界面结构:阳离子互化与粗糙
Deep learning of interface structures from the 4D STEM data: cation intermixing vs. roughening
论文作者
论文摘要
复杂氧化物中的界面结构仍然是冷凝物质物理研究的活性区域之一,这在很大程度上取决于扫描透射电子显微镜(STEM)的最新进展。然而,沿给定方向投射结构的茎对比的性质排除了可能的结构模型的分离。在这里,我们利用对模拟的4D扫描透射电子显微镜(STEM)数据集训练的深卷积神经网络(DCNN)来预测接口的结构描述。我们专注于使用动力学衍射理论和利用高性能计算来模拟数千个可能的4D STEM数据集以训练DCNN以学习模拟基于模拟的基础结构的属性,以使用动力学衍射理论和利用高性能计算来研究Laalo3和SRTIO3之间的广泛研究的界面。我们在模拟数据上验证了DCNN,并表明(精度> 95%的精度)可以从化学扩散的界面中识别出物理上的粗糙,并在确定界面内埋入的步骤位置时达到85%的精度。此处显示的方法是通用的,可以适用于存在正向模型的任何反向成像问题。
Interface structures in complex oxides remain one of the active areas of condensed matter physics research, largely enabled by recent advances in scanning transmission electron microscopy (STEM). Yet the nature of the STEM contrast in which the structure is projected along the given direction precludes separation of possible structural models. Here, we utilize deep convolutional neural networks (DCNN) trained on simulated 4D scanning transmission electron microscopy (STEM) datasets to predict structural descriptors of interfaces. We focus on the widely studied interface between LaAlO3 and SrTiO3, using dynamical diffraction theory and leveraging high performance computing to simulate thousands of possible 4D STEM datasets to train the DCNN to learn properties of the underlying structures on which the simulations are based. We validate the DCNN on simulated data and show that it is possible (with >95% accuracy) to identify a physically rough from a chemically diffuse interface and achieve 85% accuracy in determination of buried step positions within the interface. The method shown here is general and can be applied for any inverse imaging problem where forward models are present.