Spatially dispersive dynamical response of hot carriers in doped graphene

Abstract

We study theoretically wave-vector and frequency dispersion of the complex dynamic conductivity tensor (DCT), ${\sigma }_{lm}(\mathbf{k},\omega )$, of doped monolayer graphene under a strong dc electric field. For a general analysis, we consider the weak ac field of arbitrary configuration given by two independent vectors, the ac field polarization and the wave vector $\mathbf{k}$. The high-field transport and linear response to the ac field are described on the base of the Boltzmann kinetic equation. We show that the real part of DCT, calculated in the collisionless regime, is not zero due to dissipation of the ac wave, whose energy is absorbed by the resonant Dirac quasiparticles effectively interacting with the wave. The role of the kinematic resonance at $\omega =v_F|\mathbf{k}|$ ($v_F$ is the Fermi velocity) is studied in detail taking into account deviation from the linear energy spectrum and screening by the charge carriers. The isopower-density curves and distributions of angle between the ac current density and field vectors are presented as a map which provides clear graphic representation of the DCT anisotropy. Also, the map shows certain ac field configurations corresponding to a negative power density, thereby it indicates regions of terahertz frequency for possible electrical (drift) instability in the graphene system.

32 pages, 9 figures, accepted to Physica E: Low-dimensional Systems and Nanostructures

References in corpus (15)

• Electric Field Effect in Atomically Thin Carbon Films
• The electronic properties of graphene
• Graphene photodetectors for high-speed optical communications
• Measurement of the Optical Conductivity of Graphene
• The optical conductivity of graphene in the visible region of the spectrum
• Space-time dispersion of graphene conductivity
• Unusual Microwave Response of Dirac Quasiparticles in Graphene
• Sum Rules for the Optical and Hall Conductivity in Graphene
• Thermally-Limited Current Carrying Ability of Graphene Nanoribbons
• Ultrafast and Nanoscale Plasmonic Phenomena in Exfoliated Graphene Revealed by Infrared Pump-Probe Nanoscopy
• Charge response function and a novel plasmon mode in graphene
• Mechanism for current saturation and energy dissipation in graphene transistors
• Role of Joule Heating on Current Saturation and Transient Behavior of Graphene Transistors
• Theoretical analysis of high-field transport in graphene on a substrate
• Semiclassical analysis of intraband collective excitations in a two-dimensional electron gas with Dirac spectrum

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