Bulk-sensitive photoemission study of A Cu3 Ru4 O12 (A=Ca, Na, and La) with heavy-fermion behavior

Takaaki Sudayama, Yuki Wakisaka, Kou Takubo, Takashi Mizokawa, Wataru Kobayashi, Ichiro Terasaki, Soutarou Tanaka, Yoshiteru Maeno, Masashi Arita, Hirofumi Namatame, Masaki Taniguchi

Research output: Contribution to journalArticle

15 Citations (Scopus)


We have studied the d -electron heavy-fermion states in A Cu3 Ru4 O12 (A=Ca, Na, and La) using x-ray photoemission spectroscopy and high-resolution photoemission spectroscopy at bulk-sensitive photon energy (7 eV). The bulk-sensitive photoemission measurements for A=Ca, Na, and La show that a resonancelike structure within a pseudogap commonly evolves in the low-temperature range where the Kadowaki-Woods relation holds. The origin of the resonancelike peak and the heavy-fermion behavior is basically attributed to the hybridization between the Cu3d and Ru4d orbitals. The A -site substitution controls the filling of the Cu3d and Ru 4d hybridized bands. Interestingly, while the resonancelike peak position roughly follows the rigid-band shift for A=Na and La, the resonancelike peak deviating from the rigid-band behavior is located just at the Fermi level as expected in a Kondo system. The difference in the resonancelike peak near the Fermi level is correlated with that in the Cu2p core-level spectra.

Original languageEnglish
Article number075113
JournalPhysical Review B - Condensed Matter and Materials Physics
Issue number7
Publication statusPublished - 2009 Aug 14
Externally publishedYes

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Bulk-sensitive photoemission study of A Cu<sub>3</sub> Ru<sub>4</sub> O12 (A=Ca, Na, and La) with heavy-fermion behavior'. Together they form a unique fingerprint.

  • Cite this

    Sudayama, T., Wakisaka, Y., Takubo, K., Mizokawa, T., Kobayashi, W., Terasaki, I., Tanaka, S., Maeno, Y., Arita, M., Namatame, H., & Taniguchi, M. (2009). Bulk-sensitive photoemission study of A Cu3 Ru4 O12 (A=Ca, Na, and La) with heavy-fermion behavior. Physical Review B - Condensed Matter and Materials Physics, 80(7), [075113]. https://doi.org/10.1103/PhysRevB.80.075113