Role of substrate strain in moderate bandwidth antiferromagnetic manganite films

High-quality moderate-bandwidth manganite Pr0.5Sr0.5MnO3 (PSMO) thin films were synthesized on two types of substrates using pulsed laser deposition. In contrast to the A-type antiferromagnetic insulator in bulk PSMO, we observed in the film under slight tensile strain a metallic behavior, which is associated with a nanoscale phase separation state having long-range percolation. In contrast, compressive strain induces insulating transport behavior and a tilted magnetic easy axis, linked to a finite-sized cluster state. It is likely that in a moderate-bandwidth manganite, the tensile strain stabilizes the orientation of orbital ordering, allowing a planar long-range metallic transport. The strain-sensitive ordering of moderate-bandwidth antiferromagnetic material presents a potential for designing electronic/magnetic devices with tunable conductivity.