Related papers: Negative dynamic Drude conductivity in pumped grap…
Electron transport in graphene under a laser-modulated barrier is studied in the presence of an energy gap, a scalar potential, and a uniaxial zigzag strain. The transfer-matrix approach is used with the boundary conditions to derive the…
We analyze the surface plasmons (SPs) propagating along the optically pumped single-graphene layer (SGL) and multiple-graphene layer (MGL) structures. It is shown that at sufficiently strong optical pumping when the real part of dynamic…
Among the different strategies used to induce the opening of a band gap in graphene, one common practice is through chemical doping. While a gap may me opened in this way, disorder-induced scattering is an unwanted side-effect that impacts…
We studied theoretically the effect of a low concentration of adsorbed polar molecules on the optical conductivity of graphene, within the Kubo linear response approximation. Our analysis is based on a continuum model approximation that…
The absence of a band gap in graphene restricts its straight forward application as a channel material in field effect transistors. In this letter, we report on a new approach to engineer a band gap in graphene field effect devices (FED) by…
We present a practical scheme to separate the contributions of the electric quadrupole-like and the magnetic dipole-like effects to the forbidden second order optical nonlinear response of graphene, and give analytic expressions for the…
Irradiation of graphene on SiO2 by 500 eV Ne and He ions creates defects that cause intervalley scattering as evident from a significant Raman D band intensity. The defect scattering gives a conductivity proportional to charge carrier…
We report a highly efficient tunable THz reflector in graphene. By applying a small gate voltage (up to 3 V), the reflectance of graphene is modulated from a minimum of 0.79% to a maximum of 33.4% using graphene/ionic liquid structures at…
The transient evolution of carriers in an intrinsic graphene under ultrafast excitation, which is caused by the collisionless interband transitions, is studied theoretically. The energy relaxation due to the quasielastic acoustic phonon…
Electron optics deals with condensed matter platforms for manipulating and guiding electron beams with high efficiency and robustness. Common devices rely on the spatial confinement of the electrons into one-dimensional channels. Recently,…
We present a general formulation to calculate the dynamic optical conductivity, beyond the linear response regime, of any electronic system whose quasiparticle dispersion is described by a two band model. Our phenomenological model is based…
Nonlinear light-matter interactions are typically enhanced by increasing the local field and its interaction time with matter. Conventional methods to achieve these goals are based on resonances or slow-light effects. However, these methods…
Ballistic semiconductor structures have allowed the realization of optics-like phenomena in electronics, including magnetic focusing and lensing. An extension that appears unique to graphene is to use both n and p carrier types to create…
We investigate non-adiabatic electron pumping in graphene generated by laser irradiation with linear polarization parallel or perpendicular to the transport direction. Transport is dominated by the spatially asymmetric excitation of…
1-loop quantum corrections are shown to induce large effects on the refraction index $n$ inside a graphene strip in the presence of an external magnetic field $B$ orthogonal to it. To this purpose, we use the tools of Quantum Field Theory…
Interband transitions of electrons in a gapped graphene monolayer are highly stimulated near the Fermi surface when a high-frequency electric wave of weak intensity and a strong constant electric field are superposed in the plane of the…
The modulation of the transmitted (reflected) radiation due to change of interband transitions under variation of carriers concentration by the gate voltage is studied theoretically. The calculations were performed for strongly doped…
Various bandstructure engineering methods have been studied to improve the performance of graphitic transparent conductors; however none demonstrated an increase of optical transmittance in the visible range. Here we measure in situ optical…
We present a new paradigm for understanding optical absorption and hot electron dynamics experiments in graphene. Our analysis pivots on assigning proper importance to phonon assisted indirect processes and bleaching of direct processes. We…
We show that plasmons in two-dimensional graphene can have net gain at terahertz frequencies. The coupling of the plasmons to interband electron-hole transitions in population inverted graphene layers can lead to plasmon amplification…