High Resolution TEM

Description

This lecture covers the principles and techniques of High Resolution Transmission Electron Microscopy (HRTEM), focusing on topics such as contrast transfer, bright field imaging, atomic resolution, Scherzer defocus, white-atom contrast, and image formation. It discusses the importance of the optical system, transfer functions, weak phase object approximation, and the impact of spherical aberration. The lecture also explores the concept of delocalization, the role of the Cs corrector in improving image quality, and the reconstruction of exit wave functions. Examples include the observation of cation ordering in ferroelectric relaxors and the use of Cs correctors to overcome aberrations in imaging gold crystals.

Official source

https://mediaspace.epfl.ch/media/0_0e7ldkak

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