Spin Density and Quantum Fluctuations in Quasi-One-Dimensional Conductors

准一维导体中的自旋密度和量子涨落

• 批准号: 05640410
• 负责人: SUZUMURA Yoshikazu
• 金额: $ 1.28万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05640410/
• 关键词: Quasi-1D Conductor; Spin Density Wave; Collective Mode; Spin Fluctuation; Phase Hamiltonian; DCNQI-Cu; Strong Correlation; Metal-Insnlator Transition; 擬一次元有機導体; DCNQI-Cu塩; 強相関電子系; アニオン格子; 金属-絶縁体; 運動量分布; DCNQI塩; 比熱; 電荷密度波; リエントラント

The role of repulsive interaction in quasi-one-dimensional organic conductors has been studied in order to examine the fluctuation of spin density in low-dimensioanl electron system. Following three subjects have been investigated. (1) The fluctuation of the commensurate spin density wave (SDW) has been examined by calculating collective modes of a Hubbard model with a quarter-filled band. The longitudinal mode shows the gap and the coexistence of the 2k_F-SDW and the 4k_F-CDW.The effect of anion lattice was examined in terms of a phase Hamiltonian. (2) A role of interchain hopping in quasi-1D organic conductors was examined by applying the phase Hamiltonian based on the bosonization to two coupled chains with the repulsive interaction of backward and forward scatterings. The competition of SDW state and superconducting state explains the phase diagram of in the quasi-1D conductors. (3) The metal-insulatortarnsition in DCNQI-Cu salts was examined by applying the slave-boson mean-field theory to the periodic Anderson model with the electron-phonon (e-p) interaction. The fact that the M-I transition is the Peierls transition in the presence of the strong correlation has been shown by calculating the reentrant transition of M-I-M,the phase diagram specific heat and magnetic susceptibility, the dimensional effect and the antiferromagnetic state. Thus we have shown the mechanism of the M-I transition.

已经研究了排斥相互作用在准二维有机导体中的作用，以便研究低二秒电子系统中自旋密度的波动。遵循三个主题。 （1）通过计算具有四分之一填充带的哈伯德模型的集体模式来检查相应旋转密度波（SDW）的波动。纵向模式显示了2K_F-SDW和4K_F-CDW的差距和共存。根据相位的hamiltonian检查了阴离子晶格的效果。 （2）通过将骨化相基于琼脂化相位的相互作用，与向后和正向散射的排斥相互作用，将链跳跃在准1D有机导体中的作用进行了检查。 SDW状态和超导状态的竞争解释了准1D导体中的相图。 （3）通过将slave-boson均值场理论应用于元素phonon（e-p）相互作用，将dcnqi-cu盐中的金属胰岛植物理论应用于周期性的安德森模型。通过计算M-I-M的重进入转变，相图特异性的热和磁敏感性，尺寸效应和抗磁磁状态，M-I转变是在存在强相关的情况下PEIERLS转变的事实。因此，我们已经显示了M-I转变的机制。

项目成果

Y.Suzumura: "Anisotropic Order Parameters for Two-Dimensional Strong Coupling Superconductors" Synthetic Metals. 71. 1635-1636 (1995)

Y.Suzumura：“二维强耦合超导体的各向异性有序参数”合成金属。

Y.Suzumura: "Metal-Insulator Transition in Organic Conductor DCNQI-Cu Salt" Synthetic Metals. 70. 1083-1084 (1995)

Y.Suzumura：“有机导体 DCNQI-Cu 盐中的金属-绝缘体转变”合成金属。

Y.Ono: "Kondo Insulator and Charge Transfer Insulator in Lattice Anderson Model" J.Phys.Soc.Jp. 63(発表予定). (1994)

Y.Ono：“格子安德森模型中的近藤绝缘体和电荷转移绝缘体”J.Phys.Soc.Jp.63（待发表）。

H.Yoshioka and Y.Suzumura: "Two Coupled Chains of Tomonaga Model" J.Phys.Soc.Jpn.Vol.63. 4298-4301 (1994)

H.Yoshioka 和 Y.Suzumura：“朝永模型的两条耦合链”J.Phys.Soc.Jpn.Vol.63。

T.Ogawa: "Peierls Transition of Strongly Correlated DCNQI-Cu Salts" J.Phys.Soc.Jpn. 63. 2066-2069 (1994)

T.Okawa：“强相关 DCNQI-Cu 盐的 Peierls 转变”J.Phys.Soc.Jpn。