日本原子力研究開発機構 (JAEA) / 量子ビーム応用研究部門
放射光科学研究ユニット / 放射光量子シミュレーショングループ
日時: | 平成19年 9月12日(水) 16:00〜 |
Date and time: | 12th Sep. (Wed.) 16:00〜 |
場所: | SPring-8, 萌光館 |
Place: | SPring-8, "HOUKOUKAN" seminar room |
Title: | Filling-dependence of the zigzag Hubbard ladder for the quasi-one-dimensional superconductor Pr2Ba4Cu7O15-δ |
講演者: | 奥西巧一 氏 (新潟大学理学部) |
Speaker: | Dr. Kouichi Okunishi (Department of Physics, Niigata University) |
Abstract: |
Recently, a novel Cu-based compound Pr2Ba4Cu7O15-δ was found to show superconductivity below about 15K. An interesting point is that the metallic conductivity is originating from the CuO zigzag-ladder part in the lyered structure, and thus the quasi-one dimensional mechanizm of the superconductivity can be expected. We investigate filling dependence of the zigzag Hubbard ladder, using density matrix renormalization group method. We then illustrate the chemical-potential vs. electron-density and spin gap vs. electron density curves, which reflect characteristic properties of the electron state. On the basis of the obtained phase diagram, we discuss the superconductivity of Pr2Ba4Cu7O15-δ.