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第29回 原研・兵県大合同コロキウム

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.