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Updated: Dec 15, 2025

Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures
Published on: February 8, 2018
Electronic coupling in square planar La4Ni3O8
M H Upton1, Junjie Zhang2,3, Hong Zheng2
1Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, United States of America.
Abstract:
A study of addexcitation in La4Ni3O8(La-438) using x-ray absorption scattering and resonant inelastic x-ray scattering (RIXS) at the Ni K-edge is presented. The incident energy dependence of thisddexcitation shows a maximum at the 1s→ 4pπtransition. Its intensity at the main edge is proportional to the amount of incident x-ray polarization parallel to thec-axis. These observations suggest that the RIXS process underlying this excitation includes a strong Ni 3d-Ni 4pCoulomb interaction and excludes the '4p-as-spectator' approximation. The dominant Ni 3dCoulomb interaction is with Ni 4pπwith limited or no interaction with the Ni 4pσ. An insulating gap closing is observed as a function of temperature.
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