Low-temperature Lanczos method for strongly correlated systems
Low-temperature Lanczos method for strongly correlated systems
复制标题
强相关系统的低温 Lanczos 方法
DOI：
10.1103/physrevb.67.161103
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发表时间：
2002
影响因子：
3.7
通讯作者：
W. Linden
中科院分区：
文献类型：
--
作者：
M. Aichhorn;M. Daghofer;H. Evertz;W. Linden
我们提出了一种改进的有限温度Lanczos方法，用于计算强关联电子系统的动态量和静态量，补充了Jaklic和Prelovsek提出的低温有限温度方法。它们结合在一起，可以在任何温度下以适度的努力进行准确的计算。作为例子，我们计算了一维Hubbard模型在半填充状态下的静态自旋关联函数和光导σRe g(ω)的正则部分，并详细说明了基态方法和有限温度方法之间的联系。利用团簇微扰理论，将有限温度谱函数推广到无限大系统，清楚地显示了自旋-电荷分离的影响。
We present a modified finite-temperature Lanczos method for the evaluation of dynamical and static quantities of strongly correlated electron systems that complements the finite-temperature method introduced by Jaklic andPrelovsek for low temperatures. Together they allow accurate calculations at any temperature with moderate effort. As an example we calculate the static spin-correlation function and the regular part of the optical conductivity σ r e g (ω) of the one-dimensional Hubbard model at half filling and show in detail the connection between the ground-state and finite-temperature method. By using cluster perturbation theory, the finite-temperature spectral function is extended to the infinite system, clearly exhibiting the effects of spin-charge separation.