Role of acoustic phonons in exotic conductivity of two-dimensional Dirac electrons

Article

关键词: GAP SEMICONDUCTING STATE;    ALPHA-(BEDT-TTF)(2)I-3 SALT;    TRANSPORT;    GRAPHENE;    PRESSURE;    SYSTEM;   

DOI  :  10.1103/PhysRevB.98.161205

来源: SCIE

【 摘 要 】

We examine the effect of acoustic phonon scattering on the conductivity of two-dimensional Dirac electrons. The temperature (T) dependence of the conductivity (sigma) is calculated using the electron Green's function with damping by both the impurity (Gamma(0)) and phonon (Gamma(ph)). For zero or small doping, on which the present Rapid Communication focuses, sigma (T) increases and becomes almost constant due to the competition between the Dirac electrons and the phonon scattering. Such strange behavior of sigma (T) is ascribed to an exotic mechanism of phonon scattering, whose momentum space is strongly reduced in the presence of a Dirac cone. For large doping, sigma decreases due to the interplay of the Fermi surface and the phonon. The unconventional T dependence of the resistivity rho (=1/sigma) for small doping is compared with that of the experiment of Dirac electrons in an organic conductor.

【 授权许可】

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