相关论文: Experimental observation of polarization-dependent…
Femtosecond time-resolved spectroscopy using 400 nm-pump and 800 nm-probe in CVD-grown multilayer graphene provides strong evidence for isotropic distribution of photoexcited carrier after initial relaxation. Indicative of such isotropic…
We demonstrated theoretically that the renormalization of the electron energy spectrum near the Dirac point of graphene by a strong high-frequency electromagnetic field (dressing field) drastically depends on polarization of the field.…
Interband optical transitions in graphene are subject to pseudospin selection rules. Impulsive excitation with linearly polarized light generates an anisotropic photocarrier occupation in momentum space that evolves at timescales shorter…
We investigate the photoconductivity of graphene within the relaxation time approximation. In presence of the inter-band transitions induced by the linearly polarized light the photoconductivity turns out to be highly anisotropic due to the…
Graphene is an ideal material to study fundamental Coulomb- and phonon-induced carrier scattering processes. Its remarkable gapless and linear band structure opens up new carrier relaxation channels. In particular, Auger scattering bridging…
Strain engineering has been recently recognized as an effective way to tailor the electrical properties of graphene. In the optical domain, effects such as strain-induced anisotropic absorption add an appealing functionality to graphene,…
For many of the envisioned optoelectronic applications of graphene it is crucial to understand the sub-picosecond carrier dynamics immediately following photoexcitation, as well as the effect on the electrical conductivity - the…
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…
Using ultrahigh magnetic fields up to 170 T and polarized midinfrared radiation with tunable wavelengths from 9.22 to 10.67 um, we studied cyclotron resonance in large-area graphene grown by chemical vapor deposition. Circular-polarization…
We investigate the polarization dependence of the carrier excitation and relaxation in epitaxial multilayer graphene. Degenerate pump-probe experiments with a temporal resolution of 30 fs are performed for different rotation angles of the…
We study quasiparticle dynamics in graphene exposed to a linearly-polarized electromagnetic wave of very large intensity. Low-energy transport in such system can be described by an effective time-independent Hamiltonian, characterized by…
While the Dirac band structure of graphene has established it as a leading platform for ultrafast optoelectronics, its non-perturbative nonlinear response under intense excitation remains poorly understood. Here, we report ultrafast…
The pressure evolution of the Raman spectrum of graphene grown by chemical vapour deposition on polycrystalline copper is investigated with the use of a polar and a non-polar pressure transmitting medium (PTM). The G and 2D Raman bands…
The low-temperature phase diagram of multilayer graphene heterostructures is largely defined by the exchange-driven instability that lifts the four-fold isospin degeneracy. Such instability gives rise to the quarter- and half-metal phases,…
Understanding the ultrafast dynamics of photoexcited charges in graphene is essential, as the microscopic mechanisms underlying these dynamics determine many of graphene's optical, optothermal, and optoelectronic properties. These are…
We study theoretically interaction of a bilayer graphene with a circularly polarized ultrafast optical pulse of a single oscillation at an oblique incidence. The normal component of the pulse breaks the inversion symmetry of the system and…
Carrier dynamics in single-layer graphene grown by chemical vapor deposition (CVD) is studied using spatially and temporally resolved pump-probe spectroscopy by measuring both differential transmission and differential reflection. By…
We present a robust and exact method for calculating the polarization function and plasmon dispersion of graphene, for an arbitrary (isotropic) non-equilibrium carrier distribution, within random phase approximation (RPA). This is…
We calculate the static polarizability of multilayer graphene and study the effect of stacking arrangement, carrier density, and onsite energy difference on graphene screening properties. At low densities, the energy spectrum of multilayer…
The dynamics of photocarriers in reduced graphene oxide thin films is studied by using ultrafast pump-probe spectroscopy. Time dependent differential transmissions are measured with sample temperatures ranging from 9 to 300 K. At each…