عنوان

Depth-resolved charge reconstruction at the LaNiO3/CaMnO3 interface

Number

LA35c5r96d

Title Proper

Depth-resolved charge reconstruction at the LaNiO3/CaMnO3 interface

General Material Designation

[Article]

First Statement of Responsibility

Chandrasena, RU; Flint, CL; Yang, W; Arab, A; Nemšák, S; Gehlmann, M; Özdöl, VB; Bisti, F; Wijesekara, KD; Meyer-Ilse, J; Gullikson, E; Arenholz, E; Ciston, J; Schneider, CM; Strocov, VN; Suzuki, Y; Gray, AX

Text of Note

© 2018 American Physical Society. Rational design of low-dimensional electronic phenomena at oxide interfaces is currently considered to be one of the most promising schemes for realizing new energy-efficient logic and memory devices. An atomically abrupt interface between paramagnetic LaNiO3 and antiferromagnetic CaMnO3 exhibits interfacial ferromagnetism, which can be tuned via a thickness-dependent metal-insulator transition in LaNiO3. Once fully understood, such emergent functionality could turn this archetypal Mott-interface system into a key building block for the above-mentioned future devices. Here, we use depth-resolved standing-wave photoemission spectroscopy in conjunction with scanning transmission electron microscopy and x-ray absorption spectroscopy, to demonstrate a depth-dependent charge reconstruction at the LaNiO3/CaMnO3 interface. Our measurements reveal an increased concentration of Mn3+ and Ni2+ cations at the interface, which create an electronic environment favorable for the emergence of interfacial ferromagnetism mediated via the Mn4+-Mn3+ ferromagnetic double exchange and Ni2+-O-Mn4+ superexchange mechanisms. Our findings suggest a strategy for designing functional Mott oxide heterostructures by tuning the interfacial cation characteristics via controlled manipulation of thickness, strain, and ionic defect states.

Date of Publication

2018

Title

Lawrence Berkeley National Laboratory

Electronic name

[Article]

275578

a

Y