Resolving the microscopic nature of electronic phase separation in the CMR manganites via 3DXRD

Colossal magnetoresistance (CMR) in the manganite perovskites arises from intrinsic electronic phase separation (EPS) occurring because of the competition between ferromagnetic conducting and antiferromagnetic orbitally ordered insulating phases, at specific doping levels. However, the very nature of the EPS state has frustrated any attempts over the past 3 decades to accurately characterise the microscopic structures of its constituents. We propose a diffraction resolved tomography experiment with nano-focused beam on ID11 to tackle this long-standing problem. The results will allow for accurate microscopic structural models of the competing states to be ascertained for the first time and will also provide a 3-dimensional map of strain fields within the electronically separated phases on a 0.1-100 μm length scale. Our insights will lead to a broader understanding of how these functional properties are linked with EPS phenomena so that these can be systematically tuned and enhanced.