학술논문
CaCu$_3$Ru$_4$O$_{12}$: a high Kondo-temperature transition metal oxide
Document Type
Working Paper
Author
Takegami, D.; Kuo, C. Y.; Kasebayashi, K.; Kim, J. -G.; Chang, C. F.; Liu, C. E.; Wu, C. N.; Kasinathan, D.; Altendorf, S. G.; Hoefer, K.; Meneghin, F.; Marino, A.; Liao, Y. F.; Tsuei, K. D.; Chen, C. T.; Ko, K. -T.; Günther, A.; Ebbinghaus, S. G.; Seo, J. W.; Lee, D. H.; Ryu, G.; Komarek, A. C.; Sugano, S.; Shimakawa, Y.; Tanaka, A.; Mizokawa, T.; Kuneš, J.; Tjeng, L. H.; Hariki, A.
Source
Phys. Rev. X 12, 011017 (2022)
Subject
Language
Abstract
We present a comprehensive study of CaCu$_3$Ru$_4$O$_{12}$ using bulk sensitive hard and soft x-ray spectroscopy combined with local-density approximation (LDA) + dynamical mean-field theory (DMFT) calculations. Correlation effects on both the Cu and Ru ions can be observed. From the Cu $2p$ core level spectra we deduce the presence of magnetic Cu$^{2+}$ ions hybridized with a reservoir of itinerant electrons. The strong photon energy dependence of the valence band allows us to disentangle the Ru, Cu, and O contributions and thus to optimize the DMFT calculations. The calculated spin and charge susceptibilities show that the transition metal oxide CaCu$_3$Ru$_4$O$_{12}$ must be classified as a Kondo system and that the Kondo temperature is in the range of 500-1000 K.
Comment: Accepted for publication in Phys. Rev. X
Comment: Accepted for publication in Phys. Rev. X