MOmentum and position REsolved mapping Transmission Electron energy loss Microscope

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A major mission of condensed-matter physics is to understand material properties via the knowledge of the energy vs. momentum (q) dispersion and lifetime of fundamental excitations. Unfortunately, none of the available techniques can be applied to emerging nanomaterials: inelastic x-ray scattering & electron energy loss spectroscopy (EELS) in reflection lack the spatial resolution whereas EELS in transmission electron microscopy lacks the needed combined spatial, energy & q-resolution. In MORE-TEM, we develop a new spectrometer enabling to map excitations q-resolved with 0.01 Å-1 resolution and q-averaged down to atomic level, at unprecedented 1 meV energy resolution and at variable temperature between 700K & 4K. This breakthrough is possible by bringing together our synergy group with complementary skills in electron microscopy, electron optics, experimental & theoretical spectroscopy. This opens the so-far unexplored possibility to investigate dispersion and lifetime of phonons, plasmons & excitons in nanomaterials including (organic) molecules, 1D nanotubes, 2D materials, heterostructures & nanocrystals in minerals with a few nm of lateral resolution on samples as thin as an atomic monolayer. Mapping out the spatial and q-landscape of primary excitations will allow us to gain control on quantum phases, like charge-density waves and superconductivity, to engineer new materials for energy (e.g. batteries), (opto-)electronic devices in (organic) electronics, and to model the physical and chemical properties of natural geological systems. This will hugely impact a wide range of applications in physics, chemistry, engineering, as well as in environmental-, geo- & material science. MORE-TEM not only implements features of a large scale facility on a cheaper table-top instrument, but it also pushes q-resolved spectroscopy to the realm of the nanoscale, providing thus a fundamentally new & unique infrastructure for the characterization and optimisation of nanomaterials.