相关论文: Extreme electron-hole drag and negative mobility i…
Spatially separated electron systems remain strongly coupled by electron-electron interactions even when they cannot exchange particles, provided that the layer separation d is comparable to a characteristic distance l between charge…
Vertical heterostructures combining different layered materials offer novel opportunities for applications and fundamental studies of collective behavior driven by inter-layer Coulomb coupling. Here we report heterostructures comprising a…
Motivated by the notion that a preponderance of Coulomb interactions might lead to hydrodynamics, we carry out an ab initio calculation of the charge carrier transport properties of the electron-hole plasma of doped graphene. We include…
Several recent experiments have reported an anomalous temperature dependence of the Coulomb drag effect in electron-hole bilayers. Motivated by these puzzling data, we study theoretically a low-density electron-hole bilayer, where electrons…
We propose a hydrodynamic model describing steady-state and dynamic electron and hole transport properties of graphene structures which accounts for the features of the electron and hole spectra. It is intended for electron-hole plasma in…
We report the observation of Coulomb drag between a two-dimensional (2D) electron gas in graphene and a one-dimensional (1D) wire composed of a carbon nanotube. We find that drag occurs when the bulk of graphene is conducting, but is…
Ballistic transport occurs whenever electrons propagate without collisions deflecting their trajectory. It is normally observed in conductors with a negligible concentration of impurities, at low temperature, to avoid electron-phonon…
We show that the plasmon spectrum of an ordinary two-dimensional electron gas (2DEG) hosted in a GaAs heterostructure is significantly modified when a graphene sheet is placed on the surface of the semiconductor in close proximity to the…
We report electrical transport measurements on GaAs/AlGaAs based electron-hole bilayers. These systems are expected to make a transition from a pair of weakly coupled two-dimensional systems to a strongly coupled exciton system as the…
Conductivity of monolayer and two-layer graphene is considered with due regard for mutual drag of band electrons and holes. Search of contribution of the drag in conductivity shows that this effect can sufficiently influence on mobility of…
We present a theory of the finite temperature thermo-electric response functions of graphene, in the hydrodynamic regime induced by electron-electron collisions. In moderate magnetic fields, the Dirac particles undergo a collective…
We review the fabrication and key transport properties of graphene double layers, consisting of two graphene monolayers placed in close proximity, independently contacted, and separated by an ultra-thin dielectric. We outline a simple band…
We have measured Coulomb drag between an individual single-walled carbon nanotube (SWNT) as a one-dimensional (1D) conductor and the two-dimensional (2D) conductor monolayer graphene, separated by a few-atom-thick boron nitride layer. The…
We report experimental data and theoretical analysis of Coulomb drag between two closely positioned graphene monolayers in weak magnetic field. Close enough to the neutrality point, coexistence of electrons and holes in each layer leads to…
We investigate transport and Coulomb drag properties of semiconductor-based electron-hole bilayer systems. Our calculations are motivated by recent experiments in undoped electron-hole bilayer structures based on GaAs-AlGaAs gated double…
Electrons and holes in clean, charge-neutral graphene behave like a strongly coupled relativistic liquid. The thermo-electric transport properties of the interacting Dirac quasiparticles are rather special, being constrained by an emergent…
We investigate the electron-hole two-stream instability (or Coulomb drag) in intrinsic bilayer graphene in the hydrodynamic regime, accounting for the effects of temperature, initial drift velocity, magnetic field, and collisions. The…
The most recognizable feature of graphene's electronic spectrum is its Dirac point around which interesting phenomena tend to cluster. At low temperatures, the intrinsic behavior in this regime is often obscured by charge inhomogeneity but…
The pseudospin of Dirac electrons in graphene manifests itself in a peculiar momentum anisotropy for photo-excited electron-hole pairs. These interband excitations are in fact forbidden along the direction of the light polarization, and are…
Electron drag between two two-dimensional electron gases in magnetic fields has been observed with a polarity opposite that for zero field. This negative drag requires that the electrons have a hole-like dispersion. Density dependence…