RQMP Research Seminar

Watching Phase Transformations with a Dynamic Transmission Electron Microscope

Kenneth Beyerlein

Centre Énergie Matériaux Télécommunications
nstitut national de la recherche scientifique

In material synthesis, thermodynamics is often not enough to explain the product phase, which instead is determined by the kinetic pathway taken during the process. Better understanding of the kinetic mechanisms and traversed energy landscape is key to realizing new materials with enhanced properties. However, we have been largely blind to the local changes happening on the atomic or nanometer scale during this process, due to the extreme temporal and spatial resolution required to capture these dynamics. The Dynamic Transmission Electron Microscope (DTEM) has been recently developed to address this challenge, and is capable of imaging irreversible transformations in materials with nanosecond and nanometer resolution. In this talk, an introduction to the operating principle of this microscope and the challenges of snapshot imaging with electrons will be given. A current benchmark of the capabilities of the DTEM at INRS will be presented, along with planned future developments. Finally, how pulsed electron probes may be useful to outrun beam damage and obtain high fidelity images of beam sensitive materials will also be discussed.