Charge Order and Photoinduced Nonlinear Dynamics in Low-Dimensional Molecular Conductors

低维分子导体中的电荷有序和光致非线性动力学

• 批准号: 12640361
• 负责人: YONEMITSU Kenji
• 金额: $ 2.37万
• 依托单位: Okazaki National Research Institutes
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12640361/
• 关键词: charge-transfer complex; platinum complex; spin-crossover complex; neutral-ionic transition; CDW-CP transition; photoinduced transition; Peierls-Hubbard models; time-dependent Schrodinger equation; モンテカルロ計算; 有機導体; 有限温度密度行列繰り込み群; 金属錯体; 電荷移動錯体 /

In (DCNQI)_2Cu, conductivity and magnetism are correlated through hybridization of π and d orbitals. In the insulator phase under high pressure, three-fold lattice distortion and paramagnetism coexist. Peierls and Mott mechanisms work cooperatively. Even the level difference between these orbitals is not optimal, self-doping takes place to stabilize this lattice-distorted phase. This fact is demonstrated by the exact diagonalization studies for a two-band Peierls-Hubbard model.In organic charge-transfer complex, TTF-CA, a transition takes place from the paraelectric neutral phase to the ferroelectric ionic phase at a low temperature or under high pressure. Photoexcitation also triggers the transition. The time-dependent Schrodinger equation is solved for an extended Peierls-Hubbard model with alternating potentials. Dynamics of charge density and lattice displacements from the ionic phase is studied to reproduce a threshold in phtoexcitation intensity. The Fourier analysis of the time- … More dependent ionicity clarifies the fast excitonic motion, the slow lattice vibration, and the even slower collective motion of neutral-ionic domain boundaries. Photoexcitation produces ionic domains with the opposite polarization to the initial one, by which the lattice order quickly decays. This is consistent with the faster evolution of the second harmonic generation than the photoreflectivity.In halogen-bridged binuclear metal complexes, various charge- and lattice-ordered phases appear depending on the ligand, halogen ion, and counter ion. The mechanisms of the respective electronic phases are investigated in Peierls-Hubbard models. Especially with iodine, platinum, and ligand pop, halogen ion, and counter ion. The mechanisms of the iodine, platinum, and ligand pop, there appear charge-density-wave (CDW) and chargepolarization (CP) phases. Photoexcitation within the hysteresis loop triggers a transition phase does not transfer charge among binuclear units at low energies, and does not grow CDW nuclei even at high energies. Less

在（DCNQI）_2Cu中，电导率和磁性通过π和d轨道的杂化而关联。在高压下的绝缘相，三重晶格畸变和顺磁性共存。Peierls和Mott机制协同工作。即使这些轨道之间的能级差不是最佳的，也会发生自掺杂以稳定这种晶格扭曲相。对两带Peierls-Hubbard模型的精确对角化研究证实了这一事实，在有机电荷转移复合物TTF-CA中，在低温或高压下发生了从顺电中性相到铁电离子相的转变。光激发也触发了这种转变。求解了含时薛定谔方程，得到了具有交变势的扩展Peierls-Hubbard模型.从离子相的电荷密度和晶格位移的动力学进行了研究，再现光激发强度的阈值。对时间的傅里叶分析- ...更多信息 依赖的离子性阐明了快激子运动、慢晶格振动和中性离子域边界的甚至更慢的集体运动。光激发产生与初始极化相反的离子域，由此晶格有序迅速衰减。这与二次谐波产生比光反射率更快的演化是一致的。在卤素桥联的双核金属配合物中，各种电荷和晶格有序相的出现取决于配体、卤素离子和抗衡离子。在Peierls-Hubbard模型中研究了相应电子相的机制。特别是与碘、铂和配体pop、卤素离子和抗衡离子。碘、铂和配体的作用机制是产生电荷密度波（CDW）和电荷极化（CP）。在磁滞回线内的光激发触发过渡相，在低能量下双核单元之间不转移电荷，并且即使在高能量下也不生长CDW核。少

项目成果

M.Mori, K.Yonemitsu: "Stability and Cation Dependence of Magnetic Orders in (Et_nMe_<4->_nZ)[Pd(dmit)_2]_2"Synthetic Metals. 120. 945-946 (2001)

M.Mori、K.Yonemitsu：“(Et_nMe_<4->_nZ)[Pd(dmit)_2]_2”中磁序的稳定性和阳离子依赖性”合成金属。

J. Kishine, P. A. Lee and X.-G. Wen: "Staggered Local Density of States around the Vortex in Underdoped Cuprates"Physical Review Letters. 86. 5365-5368 (2001)

J. Kishine、P. A. Lee 和 X.-G.

K. Yonemitsu and J. Kishine: "Charge Gap and Dimensional Crossovers in Quasi-One-Dimensional Organic Conductors"Journal of Physics and Chemistry of Solids. 62. 99-104 (2001)

K. Yonemitsu 和 J. Kishine：“准一维有机导体中的电荷间隙和维度交叉”固体物理与化学杂志。

M.Kuwabara and K. Yonemitsu: "Charge Ordering and Optical Conductivity of MMX Chains"Physics in Local Lattice Distortions (H. Oyanagi and A. Bianconi, Eds., American Institute of Physics, New York). 465-469 (2001)

M.Kuwabara 和 K. Yonemitsu：“MMX 链的电荷排序和光导率”局部晶格畸变物理学（H. Oyanagi 和 A. Bianconi，编辑，美国物理研究所，纽约）。

K. Yonemitsu: "Quantum and Thermal Charge-Transfer Fluctuations for Neutral-Ionic Phase Transitions in the One-Dime nsional Extende d Hubbard Model with Alternating Potentials"Physical Review B. 65. 085105-085111 (2002)

K. Yonemitsu：“具有交替电势的一维扩展哈伯德模型中中性离子相变的量子和热电荷转移波动”物理评论 B. 65. 085105-085111 (2002)