Filling-Control Metal-Insulator Transition in the Hubbard Model Studied by the Operator Projection Method
Filling-Control Metal-Insulator Transition in the Hubbard Model Studied by the Operator Projection Method
复制标题
算子投影法研究的哈伯德模型中的填充控制金属-绝缘体转变
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
M. Imada
中科院分区：
文献类型：
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作者：
S. Onoda;M. Imada
用算符投影方法研究了Hubbard模型中填充控制金属-绝缘体相变（MIT）的热力学和动力学性质。这是一个多体系统的非微扰分析方法。本理论将MIT的Mott-Hubbard、Brinkman-Rice和斯莱特图象统一到一个统一的框架中，并再现了自旋-电荷涨落引起的低能窄带。在半填充时，单粒子谱A（ω，k）表明随着温度的降低，在能量ω和动量k的平面上形成了两个Hubbard带和它们的反铁磁阴影，它们被Mott能隙分开。这四个带在色散中分裂成两个低能窄带和两个类SDW带。在接近半充满时，低能窄带在低温下持续存在。这个窄带在（π，0）和（0，π）动量附近具有特别弱的色散和大的权重。这些低能量激发的速度显示…
Thermodynamic and dynamical properties of filling-control metal-insulator transition (MIT) in the Hubbard model are studied by the operator projection method, especially in two dimensions. This is a non-perturbative analytic approach to many-body systems. The present theory incorporates the Mott–Hubbard, Brinkman–Rice and Slater pictures of the MIT into a unified framework, together with reproducing low-energy narrow band arising from spin-charge fluctuations. At half filling, single-particle spectra A (ω, k ) show formation of two Hubbard bands and their antiferromagnetic shadows separated by a Mott gap in the plane of energy ω and momentum k with lowering temperatures. These four bands produce splitting to two low-energy narrow bands and two SDW-like bands in the dispersion. Near half filling, the low-energy narrow band persists at low temperatures. This narrow band has a particularly weak dispersion and large weights around (π, 0) and (0, π) momenta. The velocity of these low-energy excitations is show...