Electron Ptychography

Thursday, August 17, 2017 - 2:00pm - 2:45pm
Lind 305
Andrew Maiden (University of Sheffield)
Relative to the rapid pace set in the X-ray and visible light regimes, developing electron ptychography into a useful, routine method for electrons has so far been a slow journey. The path has been hampered by hurdles such as inelastic and dynamical scattering, instrument instabilities and limited beam coherence, as well as by the sub-nanometer resolutions that electron microscopists expect. Today, however, the route is being cleared using advances from the X-ray and visible light regions of the spectrum, and momentum is beginning to build. In this talk I will discuss the trials and tribulations of ptychography on the Transmission Electron Microscope (TEM), I will present our latest results and suggest how they can be improved, and I will explain the potential advantages of our approach over through-focus and off-axis holography. I will also describe the sequential 'PIE' algorithms we use to reconstruct our electron phase images and recent advances that accelerate their convergence rates.