Antiferromagnetic fluctuations in the one-dimensional Hubbard model

• Main Authors: Václav Janiš, Antonín Klíč, Jiawei Yan
• Format: Article
• Language: English
• Published: AIP Publishing LLC 2020-12-01
• Series: AIP Advances
• Online Access: http://dx.doi.org/10.1063/9.0000019

We study the low-temperature critical behavior of the one-dimensional Hubbard model near half filling caused by enhanced antiferromagnetic fluctuations. We use a mean-field-type approximation with a two-particle self-consistency renormalizing the bare interaction. It allows us to control a transition from high to low temperatures as well as from weak to strong-coupling. We show that there is a crossover temperature T0 = t exp{−1/Uρ(0)} for arbitrary interaction U > 0 and the bare density of states at the Fermi energy ρ(0) > 0. The solution at lower temperatures goes over to strong coupling and approaches a quantum critical point with the diverging staggered susceptibility and a gap in the excitation spectrum at zero temperature.