MagTEM2 - the next generation microscope for imaging functional materials

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Correlating a material's atomic-scale structure to its functionality is central to our understanding of the physical and chemical world, and hence to most technological development. Scanning transmission electron microscopy (STEM) now dominates high resolution materials characterisation in the physical sciences, routinely revealing structural details that are otherwise indiscernible. It excels in the analysis of aperiodic structures including defects, inhomogeneities and interfaces that are below the resolution of other microscopies and cannot be studied using diffraction. These structures are important because they often dominate a material's properties, for better or worse. Atomic-scale resolution also underpins the development of devices, which may now contain features of only a few tens of atoms in dimension, often to harness quantum effects that can only be controlled on the nanoscale.Frustratingly, many materials remain inaccessible to atomic resolution STEM. One example is that the magnetic fields used to focus a STEM instrument interfere with magnetic samples, so that their intrinsic behaviour cannot be studied. We propose to capitalise on our expertise to address this problem. First, we will exploit improved electron lens designs to provide a three-fold improvement in 'field-free' imaging resolution. We will be able to visualise a sample's own electromagnetic fields on the atomic scale, facilitating novel studies of magnetic, quantum, microelectronic and plasmonic technologies alongside geological and chemical samples with nano-magnetic properties. An improved sensitivity to magnetic structure will enable the analysis of challenging samples such as synthetic antiferromagnets and low moment materials, which are of technological importance. We will also enhance time resolution and sensitivity by integrating the latest noise-free electron detectors for imaging and spectroscopy, providing enhanced capabilities for high-speed, high sensitivity analysis, particularly of delicate, beam-sensitive materials. We have been at the forefront of development in both of these areas and are exceptionally well-placed to grow an acknowledged UK research strength.