English  |  正體中文  |  简体中文  |  全文笔数/总笔数 : 55184/89457 (62%)
造访人次 : 10676444      在线人数 : 86
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library & TKU Library IR team.
搜寻范围 查询小技巧:
  • 您可在西文检索词汇前后加上"双引号",以获取较精准的检索结果
  • 若欲以作者姓名搜寻,建议至进阶搜寻限定作者字段,可获得较完整数据
  • 进阶搜寻


    jsp.display-item.identifier=請使用永久網址來引用或連結此文件: http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/27677


    题名: High-temperature superconductivity in the generalized negative U Hubbard model
    其它题名: 高溫超導在廣義負U Hubbard模型下之研究
    作者: Kocharian, A. N.;楊棨;Yang, Chi
    贡献者: 淡江大學物理學系
    关键词: Negative U Hubbard Hamiltonian;Mixed valence;Interacting fermions;Bipolaron superconductivity;Phase transitions
    日期: 1995-11-05
    上传时间: 2009-12-31 10:36:36 (UTC+8)
    出版者: Elsevier
    摘要: A new mechanism of superconductivity in high-temperature superconducting oxides (HTSCs) with partially occupied electrons in the p and d orbitals is proposed in the generalized negative U Hubbard model, including orbital degeneracy and the strong intra-atomic attraction. Our approach allows also the introduction, in a consistent way, of the orbital mixing (hybridization) between p and d bands (orbitals). The effective anisotropic Heisenberg XYZ model consisting of pseudo-orbital variables is obtained up to second order by small parameters for arbitrary concentration of particles using unitary transformation in the strong interaction limit. The ground-state energy and the partition function are obtained in the generalized mean field approximation by introducing diagonal charge-ordering parameter η and off-diagonal superconducting order parameter Δ. The self-consistent equations are analyzed and the phase diagram in the ground state and at finite temperatures for arbitrary relations between p and d bandwidths (parameter anisotropicity g) are obtained. The competition between superconducting and charge-ordering correlations for spin and orbital variables gives rise to many different pure and intermediate phases. The proposed model elucidates the role of hybridization and orbital variables on the mechanism of HTSC.
    關聯: Materials Chemistry and Physics 42(2), pp.134-137
    DOI: 10.1016/0254-0584(95)01570-1
    显示于类别:[物理學系暨研究所] 期刊論文

    文件中的档案:

    档案 描述 大小格式浏览次数
    0KbUnknown239检视/开启
    index.html0KbHTML81检视/开启

    在機構典藏中所有的数据项都受到原著作权保护.

    TAIR相关文章

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library & TKU Library IR teams. Copyright ©   - 回馈