Study on the d-p model by the Numerical Diagonalization Method

数值对角化法研究d-p模型

• 批准号: 08640484
• 负责人: SANO Kazuhiro
• 金额: $ 1.15万
• 依托单位: Mie University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08640484/
• 关键词: High-Tc Superconductivity; Correlated Electron Systems; d-p model; Numerical Diagonalization

HEAD INVESTIGATOR REGISTERED NUMBER 40201537 NAME Kazuhiro, Sano Department of Physics Engineering, Mie University Assistant ProfessorToward the clarification of the mechanism of the high temperature superconductivity, we investigate the one-dimensional d-p model by the numerical diagonalization method. The model contains electron hopping between copper (d-) site and oxygen (p-) site and repulsive Coulomb interaction on both sites. In addition, it contains the nearest-neighbor-p interaction and the hopping tpp between the nearest-neighbor p sites. It is known as a good target for investigating the possible mechanism of the high-Tc superconductivity.By calculating the paring correlation functions and the critical exponent based on the Luttinger liquid relations, we analyzed the superconducting state induced by the effect of the large repulsion Ud at the d-site in cooperation with the transfer energy tpp. We have found that the superconducting correlation is dominant in the proximity of the parameter region where the renormalized band becomes flat. The behavior of various types of the paring correlation functions suggests that the singlet paring between the nearest neighbor p sites is the most relevant to the superconducting state.We have also found that the low energy physics of the d-p model is well described by the t-J model. The narrowing of the effective bandwidth leads to the enhancement of the value of the effective superexchange interaction over the effective transfer J/t. It may originate the superconductivity in case of the d-p model as well as the enhancement of J/t causes the superconductivity in the case of the t-J model.

校长登记号40201537姓名三重大学物理工学系佐野和弘助教为了阐明高温超导的机理，我们用数值对角化方法研究了一维d-p模型。该模型包含铜（d-）位和氧（p-）位之间的电子跳跃和两个位置上的排斥库仑相互作用。此外，它还包含了最近邻p相互作用和最近邻p点之间的跳跃tpp。通过计算基于Luttinger液体关系的配对关联函数和临界指数，分析了d位大排斥Ud与转移能tpp共同作用下的超导态.我们发现，超导关联是占主导地位的参数区域附近的重整化带变得平坦。各种类型的配对关联函数的行为表明，最近邻p格点之间的单重配对与超导态最相关，我们还发现d-p模型的低能物理可以用t-J模型很好地描述。有效带宽的变窄导致有效超交换相互作用的值相对于有效传递J/t的增大。在d-p模型下，这可能是超导电性的起源;在t-J模型下，J/t的增大可能是超导电性的起源。

项目成果

K.Sano: "Possible Phase Diagram (fat-J Ladder Model" J.Phys.Soc.Jpn.Vol.65. 1146-1149 (1996)

K.Sano：“可能的相图（fat-J 阶梯模型”J.Phys.Soc.Jpn.Vol.65.1146-1149（1996）

Ken´ichi Takano: "Determination of Exchange Parameters from Magnetic Susceptibility" Journal of the Physical Society of Japan. Vol.66,No.6. 1846-1847 (1997)

Ken´ichi Takano：“根据磁化率确定交换参数”，日本物理学会杂志，第 66 卷，第 6 期（1997 年）。

K.Sano and Y.Ono: "Superconductivity of the One-Dimensional d-p Model with p-p transfer II" J.Phys.Soc.Jpn.Vol.67. 4151-4156 (1998)

K.Sano 和 Y.Ono：“具有 p-p 传递 II 的一维 d-p 模型的超导性”J.Phys.Soc.Jpn.Vol.67。

Kazuhiro Sano: "Superconductivity of the One-Dimensional d-p model with p-p transter" Journal of the physical Society of Japan. Vol.67,No.2. 389-392 (1998)

Kazuhiro Sano：“带有 p-p 转换器的一维 d-p 模型的超导性”日本物理学会杂志。

Ken'ich Takano: "Determination of Exchange Parameters from Magnetic Susceptiblity" Journal of the Physical Society of Japan. Vol.66. No.6. 1846-1847 (1997)

Kenich Takano：“根据磁化率确定交换参数”日本物理学会杂志。