Crossover from Antiferromagnetic Phase to Fermiology Regime in a Weakly Coupled Half-Filled Chain System

Jun-ichiro Kishine; Kenji Yonemitsu

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Crossover from Antiferromagnetic Phase to Fermiology Regime in a Weakly Coupled Half-Filled Chain System

Jun-ichiro Kishine·Kenji Yonemitsu

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Abstract

Effects of the electron-electron umklapp process on dimensional crossovers caused by the interchain one-particle hopping, $t_{\perp}$, in a weakly-coupled half-filled chain system have been studied, based on the perturbative renormalization-group approach. The variance of $t_\perp$ and the umklapp process under scaling is taken into account. We found that the intrachain umklapp process causes a finite crossover value of $t_\perp$, $t_{\perp cr}$. For $t_{\perp} t_{\perp c}$, the system undergoes a crossesover from the TL liquid to the Fermiology regime where the interchain propagation of a quasi-particle is coherent. We discuss relevance of the present result to the experimentally suggested, pressure-induced crossover phenomena in the quasi-one-dimensional organic systems.

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Jun-ichiro Kishine, Kenji Yonemitsu. 1998-02-18. Crossover from Antiferromagnetic Phase to Fermiology Regime in a Weakly Coupled Half-Filled Chain System. https://arxiv.org/abs/cond-mat/9802186

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