• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Physical review. B, Condensed Matter And Materals Physics >Physics of cuprates with the two-band Hubbard model: The validity of the one-band Hubbard model
【24h】

Physics of cuprates with the two-band Hubbard model: The validity of the one-band Hubbard model

机译：两波段Hubbard模型的铜价的物理学：单波段Hubbard模型的有效性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We calculate the properties of the two-band Hubbard model using the dynamical cluster approximation. The phase diagram resembles the generic phase diagram of the cuprates, showing a strong asymmetry with respect to electron- and hole-doped regimes, in agreement with experiment. Asymmetric features are also seen in one-particle spectral functions and in the charge, spin, and d-wave pairing-susceptibility functions. We address the possible reduction of the two-band model to a low-energy single-band one, as it was suggested by Zhang and Rice. Comparing the two-band Hubbard model properties with the single-band Hubbard model ones, we have found similar low-energy physics provided that the next-nearest-neighbor hopping term t' has a significant value (t'/t ≈ 0.3). The parameter t' is the main culprit for the electron-hole asymmetry. However, a significant value of t' cannot be provided in a strict Zhang and Rice [Phys. Rev. B 37, R3759 (1988); 41, 7243 (1990)] picture where the extra holes added into the system bind to the existing Cu holes forming local singlets. We note that by considering approximate singlet states, such as plaquette states, reasonable values of t', which capture qualitatively the physics of the two-band model, can be obtained. We conclude that a single-band t -t'-U Hubbard model captures the basic physics of the cuprates concerning superconductivity, antiferromag-netism, pseudogap, and electron-hole asymmetry, but is not suitable for a quantitative analysis or to describe physical properties involving energy scales larger than about 0.5 eV.
机译：我们使用动态聚类近似来计算两波段Hubbard模型的属性。该相图类似于铜酸盐的通用相图，与实验一致，显示出相对于电子和空穴掺杂区的强烈不对称性。在单粒子光谱函数以及电荷，自旋和d波对磁化率函数中也可以看到非对称特征。正如Zhang和Rice所建议的，我们讨论了将两波段模型简化为低能耗单波段模型的问题。将两波段Hubbard模型的特性与单波段Hubbard模型的特性进行比较，我们发现类似的低能物理条件是，下一个最近邻居跳跃项t'具有显着的值（t'/ t≈0.3）。参数t'是电子-空穴不对称性的主要原因。然而，严格的Zhang and Rice [Phys。 B 37版，R3759（1988）； 41，7243（1990）]图片，其中添加到系统中的多余空穴与形成局部单线态的现有Cu空穴结合。我们注意到，通过考虑近似的单重态，例如球状态，可以获得定性地捕获两频带模型的物理性质的t'的合理值。我们得出的结论是，单波段t -t'-U Hubbard模型捕获了有关超导性，反铁磁性，伪间隙和电子-空穴不对称的铜酸盐的基本物理原理，但不适用于定量分析或描述物理性质涉及的能量规模大于约0.5 eV。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号