## 抄録

Electronic states of the CoO_{2} plane in Na_{x} CoO_{2} are investigated on the basis of the triangular lattice 11-band d-p model by using the second order perturbation (SOP) and the random phase approximation (RPA). Due to the effect of the in-plane ferromagnetic fluctuations enhanced for 0.6 ≲ x ≲ 0.75, the quasiparticle dispersion near the Γ-point is strongly reduced to yield an almost flat dispersion just above the fermi level. With increasing x, the electronic specific heat coefficient γ increases towards the critical doping x_{c} ∼ 0.75 above which the in-plane ferromagnetism takes place. We also find that the six small hole pockets near the K-point are stabilized due to the electron correlation effect within both the SOP and the RPA.

本文言語 | English |
---|---|

ページ（範囲） | 3317-3320 |

ページ数 | 4 |

ジャーナル | Journal of Physics and Chemistry of Solids |

巻 | 69 |

号 | 12 |

DOI | |

出版ステータス | Published - 2008 12月 |

外部発表 | はい |

## ASJC Scopus subject areas

- 化学 (全般)
- 材料科学（全般）
- 凝縮系物理学

## フィンガープリント

「Effect of ferromagnetic spin fluctuations on the electronic states in Na_{x}CoO

_{2}based on two-dimensional triangular lattice 11-band d-p model」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。