Probing single-unit-cell resolved electronic structure modulations in oxide superlattices with standing-wave photoemission

Autor: Alexander X. Gray, Ravini U. Chandrasena, Steven J. May, R. dos Reis, Eun Ju Moon, James M. Rondinelli, Vladimir N. Strocov, Mingqiang Gu, Marius-Adrian Husanu, Jim Ciston, Weibing Yang, Arian Arab, Eric M. Gullikson, Slavomír Nemšák
Rok vydání: 2019
Předmět:
Zdroj: Physical Review B, vol 100, iss 12
ISSN: 2469-9969
2469-9950
DOI: 10.1103/physrevb.100.125119
Popis: Author(s): Yang, W; Chandrasena, RU; Gu, M; Dos Reis, RMS; Moon, EJ; Arab, A; Husanu, MA; Nemsak, S; Gullikson, EM; Ciston, J; Strocov, VN; Rondinelli, JM; May, SJ; Gray, AX | Abstract: Control of structural coupling at complex-oxide interfaces is a powerful platform for creating ultrathin layers with electronic and magnetic properties unattainable in the bulk. However, with the capability to design and control the electronic structure of such buried layers and interfaces at a unit-cell level, a new challenge emerges to be able to probe these engineered emergent phenomena with depth-dependent atomic resolution as well as element- and orbital selectivity. Here, we utilize a combination of core-level and valence-band soft x-ray standing-wave photoemission spectroscopy, in conjunction with scanning transmission electron microscopy, to probe the depth-dependent and single-unit-cell resolved electronic structure of an isovalent manganite superlattice [Eu0.7Sr0.3MnO3/La0.7Sr0.3MnO3]×15 wherein the electronic-structural properties are intentionally modulated with depth via engineered oxygen octahedra rotations/tilts and A-site displacements. Our unit-cell resolved measurements reveal significant transformations in the local chemical and electronic valence-band states, which are consistent with the layer-resolved first-principles theoretical calculations, thus opening the door for future depth-resolved studies of a wide variety of heteroengineered material systems.
Databáze: OpenAIRE