Seki Takehito, Khare Kushagra, Murakami Yoshiki O, Toyama Satoko, Sánchez-Santolino Gabriel, Sasaki Hirokazu, Findlay Scott D, Petersen Timothy C, Ikuhara Yuichi, Shibata Naoya
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Tokyo, 113-8656, Japan; PRESTO, Japan Science and Technology Agency, Kawaguchi, 332-0012, Japan.
School of Physics and Astronomy, Monash University, Clayton, Victoria, 3800, Australia.
Ultramicroscopy. 2022 Oct;240:113580. doi: 10.1016/j.ultramic.2022.113580. Epub 2022 Jun 23.
We propose a linear imaging theory for differential phase contrast under the weak-phase-weak-amplitude object approximation. Contrast transfer functions are defined for thin and thick weak objects, and they successfully describe several imaging characteristics of differential phase contrast. We discuss the defocus dependence of the contrast for several examples: atomic resolution, a p-n junction, a heterointerface, and grain boundaries. Understanding the imaging characteristics helps in adjusting aberrations in DPC STEM.
我们提出了一种在弱相位-弱振幅物体近似下的微分相衬线性成像理论。针对薄和厚的弱物体定义了对比度传递函数，它们成功地描述了微分相衬的几种成像特性。我们针对几个例子讨论了对比度对散焦的依赖性：原子分辨率、p-n结、异质界面和晶界。了解成像特性有助于在微分相衬扫描透射电子显微镜（DPC STEM）中调整像差。
