• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Electron-electron and electron-phonon interactions in highly correlated quasi-one-dimensional transition metal compounds.
【24h】

Electron-electron and electron-phonon interactions in highly correlated quasi-one-dimensional transition metal compounds.

机译：高度相关的准一维过渡金属化合物中的电子-电子和电子-声子相互作用。

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

In this dissertation, we study the one-dimensional (1-D) Peierls-Hubbard (PH) Hamiltonian in the strong-coupling regime (large-to-infinite-Hubbard-U) with applications to the following two quasi-one-dimensional transition metal compounds: Vanadium dioxide (VO{dollar}sb2){dollar} and the halogen-bridged transition metal linear chain complexes (the MX materials). We focus our study on the effects of electron-electron and electron-phonon correlations in the various competing symmetry-breaking phases in the ground state, as well as the topological excitations corresponding to local defect states of the system which determine the optical and transport properties, and doping behavior of the system.; In Chapter 2, we propose an intermediate-to-strong-coupling, spin-Peierls theory for VO{dollar}sb2{dollar} in its low-temperature phase, and find a spectrum of low-lying magnetic excitations corresponding to local defect states in the multi-photon spectrum. In Chapters 3 and 4, we study the 1-D, two-band PH model at 3/4-filling in the large-U limit with applications to certain MX materials. In the charge-degrees of freedom, both the continuum theory as well as discreteness effects of the lattice are examined. In addition to obtaining irrationally charged soliton-antisoliton (SS) pairs in the continuum theory, a massive, localized polaron is found which is missing from the continuum limit. In the spin-degrees of freedom, we study ground-state magnetic ordering as well as the low-lying magnetic excitation spectrum. Two types of charge-transfer instabilities of the system are also discussed.
机译：本文研究了强耦合态（大到无限Hubbard-U）中的一维（1-D）Peierls-Hubbard（PH）哈密顿量及其在以下两个拟一维中的应用过渡金属化合物：二氧化钒（VO {dollar} sb2）{dollar}和卤素桥联的过渡金属线性链络合物（MX材料）。我们将研究重点放在基态的各种竞争性对称破坏相中电子-电子和电子-声子相关性的影响，以及与确定光学和传输性质的系统局部缺陷状态相对应的拓扑激发，以及系统的掺杂行为。在第2章中，我们针对VO {dollar} sb2 {dollar}处于低温相的过程提出了一种中到强耦合的自旋Peierls理论，并找到了与局部缺陷状态相对应的低层磁激发光谱在多光子光谱中在第3章和第4章中，我们研究了在大U极限内以3/4填充的1-D，两波段PH模型，并应用于某些MX材料。在电荷自由度中，检验了连续论和晶格的离散效应。除了在连续论中获得不合理带电的孤子-反孤子对（SS）之外，还发现了一个巨大的局部极化子，该极化子从连续子极限中丢失。在自旋自由度中，我们研究了基态的磁有序性以及低地磁激发谱。还讨论了系统的两种类型的电荷转移不稳定性。

著录项

  • 作者

    Shi, Jia.;

  • 作者单位

    University of California, Los Angeles.;

  • 授予单位 University of California, Los Angeles.;
  • 学科 Physics Condensed Matter.
  • 学位 Ph.D.
  • 年度 1992
  • 页码 179 p.
  • 总页数 179
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 O49;
  • 关键词

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