Journal of the Physical Society of Japan
Antiferromagnetic Phase Transition and Crossover to Fermi Liquid Phase in a Weakly Coupled Half-Filled Chain System
Jun‐ichiro Kishine, Kenji Yonemitsu
Abstract
Effects of the intrachain electron-electron umklapp process and the interchain one-particle hopping, t ⊥ , in a weakly coupled half-filled chain system have been studied, based on the perturbative renormalization-group approach. By solving the scaling equations, we found that the intrachain umklapp process strongly suppresses an interchain one-particle process and causes a finite critical value for t ⊥ , t ⊥ c . For t ⊥ < t ⊥ c , as the temperature decreases, the system undergoes a phase transition into an antiferromagnetic long-range-ordered phase at a transition temperature T N which increases with the increasing t ⊥ . On the other hand, for t ⊥ > t ⊥ c , the system undergoes a crossover to the Fermi liquid phase where the interchain coherent propagation of quasi-particles occurs.