Go Ara, Jeon Gun Sang
Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea.
J Phys Condens Matter. 2009 Dec 2;21(48):485602. doi: 10.1088/0953-8984/21/48/485602. Epub 2009 Nov 11.
The one-dimensional half-filled Hubbard model is considered at zero temperature within the cellular dynamical mean-field theory (CDMFT). By the computation of the spectral gap and the energy density with various cluster and bath sizes we examine the accuracy of the CDMFT in a systematic way, which proves the accurate description of the one-dimensional systems by the CDMFT with small clusters. We also calculate the spectral weights in a full range of the momentum for various interaction strengths. The results do not only account for the spin-charge separation, but they also reproduce all the features of the Bethe ansatz dispersions, implying that the CDMFT provides an excellent description of the spectral properties of low-dimensional interacting systems.
在元胞动力学平均场理论(CDMFT)框架下,研究了零温下的一维半填充哈伯德模型。通过计算不同团簇和浴尺寸下的能隙和能量密度,我们系统地检验了CDMFT的准确性,结果证明了小团簇的CDMFT能够准确描述一维系统。我们还计算了不同相互作用强度下全动量范围内的谱权重。结果不仅解释了自旋-电荷分离现象,还再现了贝塞耳假设色散的所有特征,这意味着CDMFT能够很好地描述低维相互作用系统的谱性质。