CoO_2-Layer-Thickness Dependence of Magnetic Properties and Possible Two Different Superconducting States in Na_xCoO_2・yH_2O(Condensed matter: electronic structure and electrical, magnetic, and optical properties)
スポンサーリンク
概要
- 論文の詳細を見る
In order to understand the experimentally proposed phase diagrams of Na_xCoO_2・yH_2O, we theoretically study the CoO_2-layer-thickness dependence of its magnetic and superconducting (SC) properties by analyzing a multiorbital Hubbard model using the random phase approximation. When the Co valence s is +3.4, we show that the magnetic fluctuation exhibits a strong layer-thickness dependence, where it is enhanced at finite (zero) momentum in the thicker (thinner) layer system. A magnetic order phase appears sandwiched by two SC phases, consistent with the experiments. These two SC phases have different pairing states, where one is the singlet extended s-wave state and the other is the triplet p-wave state. On the other hand, only a triplet p-wave SC phase with a dome-shaped behavior of T_c is predicted when s=+3.5, which is also consistent with the experiments. Controversial experimental results on the magnetic properties are also discussed.
- 社団法人日本物理学会の論文
- 2007-01-15
著者
-
OGATA Masao
Department of Physics, University of Tokyo
-
MOCHIZUKI Masahito
RIKEN
-
Ogata Masao
Department Of Basic Science Graduate School Of Arts And Sciences The University Of Tokyo
関連論文
- Numerical Study of Current-Induced Domain-Wall Dynamics : Crossover from Spin Transfer to Momentum Transfer(Condensed matter: electronic structure and electrical, magnetic, and optical properties)
- Formation of Non-Unitary State near the Upper-Critical Field of Sr_2RuO_4(Condensed Matter : Electronic Structure, Electrical, Magnetic and Optical Properties)
- Precise Control of Band Filling in Na_xCoO_2(Condensed matter: electronic structure and electrical, magnetic, and optical properties)
- Human Herpesvirus 6 in Hematological Malignancies
- Fermi-Surface Reconstruction in the Periodic Anderson Model(Condensed matter: electronic structure and electrical, magnetic, and optical properties)
- Normal-State Spin Dynamics of Five-Band Model for Iron Pnictides
- Quantum Monte Carlo Study of the Quasi-One-Dimensional Superconductivity(Condensed matter: electronic structure and electrical, magnetic, and optical properties)
- "Unscreening" Effect of Coulomb Interaction on Fe-Pnictide Superconductor(Condensed matter: electronic structure and electrical, magnetic, and optical properties)
- Phase Diagram of the Triangular t-J Model with Multiple Spin Exchange in the Doped-Mott Region(Condensed matter: structure and mechanical and thermal properties)
- Mott Transitions and d-Wave Superconductivity in Half-Filled-Band Hubbard Model on Square Lattice with Geometric Frustration(Condensed matter: electronic structure and electrical, magnetic, and optical properties)