An atomic-level platform for probing intertwined orders in correlated quantum materials – ImagingQM

Correlated Quantum Materials (CQM) encompasses a large variety of materials systems in which electronic correlations and/or topology yield exotic physics, such as unconventional superconductors, multiferroic compounds, with novel magnetic and electronic orders. Engineering such materials through artificial thin-film heterostructures and more generally symmetry breaking is a promising way to tailor their extraordinary properties. Such efforts significantly rely on the guidance from spatially resolved characterisation of various orders (e.g. charge, lattice, orbital, spin) present in these CQM. To this purpose, however, the full potential of achieving sub-nanometre scale or atomic resolution, required for nanomaterials or thin films, is still yet to be unleashed.
In this project, we aim to leverage several technical advancements to push the frontier; we will leverage the low temperature high-resolution scanning transmission electron microscopy (STEM) and spectroscopy (e.g. EELS) techniques. The FR team will operate STEM at low temperatures giving access to a broad range of electronic phases that emerge during the cooling of the QCM such as charge ordered phases. Several developments will be implemented to maintain the spatial resolution during STEM-EELS (micro-)spectroscopy. For establishing and testing the state-of-the-art platform, thin films of manganites or layered cobaltates (grown by the HK team, and in some case by the TU-Wien group with a complementary approach based on sputtering) in which electron, spin and orbital orders are relatively known will be firstly investigated as ‘proof-of-concept’ systems. Furthermore, we will search for additional members of the nickelate superconductors, recently discovered by the HK team, with the presence of various possible intertwined phases. Through this project, we expect to gain significant new insights, which are otherwise challenging to obtain by other means, into the origin of high-temperature superconductivity.