Ejima S, Hager G, Fehske H
Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, 17489 Greifswald, Germany.
Phys Rev Lett. 2009 Mar 13;102(10):106404. doi: 10.1103/PhysRevLett.102.106404. Epub 2009 Mar 10.
We solve a very general two-channel fermion-boson model describing charge transport within some background medium by means of a refined pseudosite density-matrix renormalization group technique. Performing a careful finite-size scaling analysis, we determine the ground-state phase diagram and convincingly prove that the model exhibits a metal-insulator quantum phase transition for the half-filled band case. In order to characterize the metallic and insulating regimes we calculate, besides the local particle densities and fermion-boson correlation functions, the kinetic energy, the charge-structure factor, the Luttinger liquid charge exponent, and the single-particle excitation gap for a one-dimensional infinite system.
我们借助一种改进的赝格点密度矩阵重整化群技术，求解了一个非常一般的双通道费米子 - 玻色子模型，该模型描述了在某种背景介质中的电荷输运。通过仔细的有限尺寸标度分析，我们确定了基态相图，并令人信服地证明该模型在半填充能带情况下呈现金属 - 绝缘体量子相变。为了刻画金属和绝缘区域，除了局部粒子密度和费米子 - 玻色子关联函数外，我们还计算了一维无限系统的动能、电荷结构因子、卢廷格液体电荷指数和单粒子激发能隙。
