Quantum phase transitions and collapse of the Mott gap in the d=1+epsilon dimensional Hubbard model with 2k(F) umklapp scattering

Article

关键词: METAL-INSULATOR TRANSITIONS;    ANDERSON LOCALIZATION;    ORGANIC CONDUCTORS;    FERMI GAS;    SYSTEMS;    EXPANSION;   

DOI  :  10.1103/PhysRevB.62.2377

来源: SCIE

【 摘 要 】

We study the low-energy asymptotics of the d=1+epsilon dimensional Hubbard model with a circular Fermi surface where there is 2k(F) umklapp scattering present a priori. Peculiarity of the d=1+epsilon dimensions is incorporated through the imbalance between the elementary particle-particle and particle-hole (PH) loops: infrared logarithmic singularity of the PH loop is smeared for epsilon>0. The one-loop renormalization-group flows indicate that a quantum phase transition from a metallic phase to the Mott insulator phase occurs at a finite on-site Coulomb repulsion U for epsilon>0. We also discuss effects of randomness.

【 授权许可】

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