Absence of Ni2+/Ni3+ charge disproportionation and possible roles of O 2p holes in La3Ni2O7-δ revealed by hard x-ray photoemission spectroscopy

D. Takegami, K. Fujinuma, R. Nakamura, M. Yoshimura, K. D. Tsuei, G. Wang, N. N. Wang, J. G. Cheng, Y. Uwatoko, T. Mizokawa

Research output: Contribution to journalArticlepeer-review

Abstract

We have investigated the electronic structure of La3Ni2O7-δ (δ≈0.07) by means of hard x-ray photoemission spectroscopy (HAXPES). Although the nominal Ni valence is close to +2.5, the Ni 2p HAXPES spectra show an absence of Ni2+/Ni3+ charge disproportionation. The Ni 2p spectral shape including the main peak and the charge-transfer satellite indicate that oxygen 2p holes are heavily involved in the transport properties. The spectral weight suppression at the Fermi level indicates that the carriers of O 2p character (mixed with Ni 3d) are affected by electronic correlation which would be associated with the density wave transition and the superconductivity controlled by pressure.

Original languageEnglish
Article number125119
JournalPhysical Review B
Volume109
Issue number12
DOIs
Publication statusPublished - 2024 Mar 15

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Fingerprint

Dive into the research topics of 'Absence of Ni2+/Ni3+ charge disproportionation and possible roles of O 2p holes in La3Ni2O7-δ revealed by hard x-ray photoemission spectroscopy'. Together they form a unique fingerprint.

Cite this