Fate of non-Fermi-liquid behavior in QED(3) at finite chemical potential

Article

关键词: QUASI-PARTICLES;    GAUGE-FIELDS;    NORMAL-STATE;    EXCITATIONS;   

DOI  :  10.1103/PhysRevB.82.075133

来源: SCIE

【 摘 要 】

The damping rate of two-dimensional massless Dirac fermions exhibit non-Fermi-liquid behavior, proportional to(1/2)(epsilon), due to gauge field at zero temperature and zero chemical potential. We study the fate of this behavior at finite chemical potential. We first calculate explicitly the temporal and spatial components of vacuum polarization functions. The analytical expressions imply that the temporal component of gauge field develops a static screening length at finite chemical potential while the transverse component remains long-ranged owing to gauge invariance. We then calculate the fermion damping rate and show that the temporal gauge field leads to normal Fermi-liquid behavior but the transverse gauge field leads to non-Fermi-liquid behavior proportional to(2/3)(epsilon) at zero temperature. This energy dependence is more regular than proportional to(1/2)(epsilon) and does not change as chemical potential varies.

【 授权许可】

Free