Dr. Ian MacLaren

University of Glasgow, School of Physics & Astronomy

STEM has typically used HAADF imaging for a very simple and interpretable contrast.  In recent years, there has also been a resurgence of interest in bright field and annular bright field imaging in STEM in order to see lighter atoms.  However, there is much more information than this in the back focal plane, and with the advent of fast direct electron detectors, it is now possible to actually record large amounts of the back focal plane and then process the dataset to extract a variety of kinds of information.  We show the uses of this for mapping magnetic fields in materials, imaging biological structures, performing atomic resolution phase-contrast imaging, and for mapping the 3D ordering in crystals.  As part of the talk, we will discuss the integration of such a detector into a modern analytical STEM, as well as how we are dealing with data handling and processing