Precise control of band filling in Na xCoO 2

Daisuke Yoshizumi, Yuji Muraoka, Yoshihiko Okamoto, Yoko Kiuchi, Jun Ichi Yamaura, Masahito Mochizuki, Masao Ogata, Zenji Hiroi

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

Electronic properties of the sodium cobaltate Na xCoO 2 are systematically studied through a precise control of band filling. Resistivity, magnetic susceptibility and specific heat measurements are carried out on a series of high-quality polycrystalline samples prepared at 200 °C with Na content in a wide range of 0:35 ≤ x ≤ 0:70. It is found that dramatic changes in electronic properties take place at a critical Na concentration x* that lies between 0.58 and 0.59, which separates a Pauli paramagnetic and a Curie-Weiss metals. It is suggested that at x* the Fermi level touches the bottom of the a 1g band at the Γ point, leading to a crucial change in the density of states across x* and the emergence of a small electron pocket around the Γ point for x > x*.

Original languageEnglish
Article number063705
JournalJournal of the Physical Society of Japan
Volume76
Issue number6
DOIs
Publication statusPublished - 2007 Jun
Externally publishedYes

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electronics
heat measurement
sodium
specific heat
magnetic permeability
heat
electrical resistivity
metals
electrons

Keywords

  • Band filling
  • Fermi surface
  • Magnetic susceptibility
  • Resistivity
  • Sodium cobaltate
  • Sommerfeld coefficient
  • Specific heat

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Yoshizumi, D., Muraoka, Y., Okamoto, Y., Kiuchi, Y., Yamaura, J. I., Mochizuki, M., ... Hiroi, Z. (2007). Precise control of band filling in Na xCoO 2 . Journal of the Physical Society of Japan, 76(6), [063705]. https://doi.org/10.1143/JPSJ.76.063705

Precise control of band filling in Na xCoO 2 . / Yoshizumi, Daisuke; Muraoka, Yuji; Okamoto, Yoshihiko; Kiuchi, Yoko; Yamaura, Jun Ichi; Mochizuki, Masahito; Ogata, Masao; Hiroi, Zenji.

In: Journal of the Physical Society of Japan, Vol. 76, No. 6, 063705, 06.2007.

Research output: Contribution to journalArticle

Yoshizumi, D, Muraoka, Y, Okamoto, Y, Kiuchi, Y, Yamaura, JI, Mochizuki, M, Ogata, M & Hiroi, Z 2007, 'Precise control of band filling in Na xCoO 2 ', Journal of the Physical Society of Japan, vol. 76, no. 6, 063705. https://doi.org/10.1143/JPSJ.76.063705
Yoshizumi D, Muraoka Y, Okamoto Y, Kiuchi Y, Yamaura JI, Mochizuki M et al. Precise control of band filling in Na xCoO 2 . Journal of the Physical Society of Japan. 2007 Jun;76(6). 063705. https://doi.org/10.1143/JPSJ.76.063705
Yoshizumi, Daisuke ; Muraoka, Yuji ; Okamoto, Yoshihiko ; Kiuchi, Yoko ; Yamaura, Jun Ichi ; Mochizuki, Masahito ; Ogata, Masao ; Hiroi, Zenji. / Precise control of band filling in Na xCoO 2 . In: Journal of the Physical Society of Japan. 2007 ; Vol. 76, No. 6.
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