An Introduction to Electron Ptychography

Abstract

Electron ptychography is a method for recovering sample phase information from 4D-STEM data, and it is becoming increasingly practical thanks to advancements in high-speed detectors. Ptychography is suitable for analyzing materials susceptible to electron beam damage, which are challenging to observe using conventional methods. Additionally, it can extract previously unobtainable information, such as sample depth details and the aberrations and modes of the incident probe, which is expected to play an increasingly crucial role in future materials science research. However, challenges regarding solution validity and quantitativeness remain, necessitating ongoing research progress. This article attempts to provide an accessible explanation of the fundamentals of ptychography, including its principles and the detailed calculations involved in direct and iterative methods.