Atomic-Scale Tuning of the Charge Distribution by Strain Engineering in Oxide Heterostructures*

Strain engineering of complex oxide heterostructures has provided routes to explore the influence of local perturbations to the materials’ physical properties. Due to the challenge of disentangling intrinsic and extrinsic effects at oxide interfaces, the combined effects of epitaxial strain and charge transfer mechanisms have been rarely studied. Here, we reveal the local charge distribution in manganite slabs by means of high-resolution scanning transmission electron microscopy and spectroscopy via investigating how the strain locally alters the electronic and magnetic properties of La₂CuO₄–La_0.5Sr_0.5MnO₃ heterostructures. The charge rearrangement results in two different magnetic phases, an interfacial ferromagnetically reduced layer and an enhanced ferromagnetic metallic region away from the interfaces. In addition, the magnitude of the charge redistribution can be controlled via epitaxial strain, which further influences the macroscopic physical properties in a way opposed to strain effects reported on single-phase films. [1]

[1] Y.-M. Wu, Y. E. Suyolcu et al., ACS Nano 2021, 15, 16228-16235.

*Y.-M. Wu and Y. E. Suyolcu contributed equally to this work.