Doped AB_2 Hubbard Chain: Spiral, Nagaoka and RVB States, Phase Separation and Luttinger Liquid Behavior

Abstract

We present an extensive numerical study of the Hubbard model on the doped AB${}_2$ chain, both in the weak coupling and the infinite-U limit. Due to the special unit cell topology, this system displays a rich variety of phases as function of hole doping ($\delta$) away from half-filling. Near half-filling, spiral states develop in the weak coupling regime, while Nagaoka itinerant ferromagnetism is observed in the infinite-U limit. For higher doping the system phase-separates before reaching a Mott insulating phase of short-range RVB states at $\delta =1/3$. Moreover, for $\delta >1/3$ we observe a crossover, which anticipates the Luttinger liquid behavior for $\delta >2/3$.

11 pages, 13 figures

References in corpus (2)

• Quasi-One-Dimensional Quantum Ferrimagnets
• Saturated Ferromagnetism from Statistical Transmutation in Two Dimensions

Cited by in corpus (1)

• Frustration-induced quantum phase transitions in a quasi-one-dimensional ferrimagnet: Hard-core boson map and the Ton ks-Girardeau limit