Transport scattering time probed through rf admittance of a graphene capacitor

Article

关键词: QUANTUM CAPACITANCE;    TRANSISTOR;    MOBILITY;   

DOI  :  10.1103/PhysRevB.83.125408

来源: SCIE

【 摘 要 】

We have investigated electron dynamics in top gated graphene by measuring the gate admittance of a diffusive graphene capacitor in a broad frequency range as a function of carrier density. The density of states, conductivity, and diffusion constant are deduced from the low-frequency gate capacitance, its charging time, and their ratio. The admittance evolves from an rc-like to a skin-effect response at GHz frequency with a crossover given by the Thouless energy. The scattering time is found to be independent of energy in the 0- to 200-meV investigated range at room temperature. This is consistent with a random mass model for Dirac fermions.

【 授权许可】

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