Related papers: Hot Dirac Fermions in Epitaxial Graphene
We establish an analogy between spectra of Dirac fermions in laser fields and an electron spectrum of graphene superlattices formed by static 1D periodic potentials. The general relations between a laser-controlled spectrum where electron…
We theoretically study various aspects of the electron-surface optical phonon interaction effects in graphene on a substrate made of polar materials. We calculate the electron self-energy in the presence of the surface phonon-mediated…
Scanning tunneling microscopy and spectroscopy have been used to investigate the femtosecond dynamics of Dirac fermions in the topological insulator Bi$_2$Se$_3$ ultrathin films. At two-dimensional limit, bulk electrons becomes quantized…
Thermodynamic properties of the electron-positron plasma (or gas) at high and very high temperatures are investigated. To achieve this goal we have derived a number of analytical formulas for the Fermi-Dirac distribution functions (or…
Graphene multilayers are grown epitaxially on single crystal silicon carbide. This system is composed of several graphene layers of which the first layer is electron doped due to the built-in electric field and the other layers are…
Topological antiferromagnetic systems, which exhibit anisotropic band structures combined with complex relativistic spin structures in momentum space, have shown strong magnetoresistance effects driven by Dirac fermion characteristics.…
We report the lattice dynamics of transition metal thin films by using the ultrafast electron diffraction. We observe a suppression of the diffraction intensity in a few picosecond after the photoexcitation, which is directly interpreted as…
Massive Dirac fermions are low-energy electronic excitations characterized by a hyperbolic band dispersion. They play a central role in several emerging physical phenomena such as topological phase transitions, anomalous Hall effects and…
Multi-layer epitaxial graphene (MEG) is investigated using far infrared (FIR) transmission experiments in the different limits of low magnetic fields and high temperatures. The cyclotron-resonance like absorption is observed at low…
We theoretically study the relaxation of high energy single particle excitations into molecules in a system of attractive fermions in an optical lattice, both in the superfluid and the normal phase. In a system characterized by an…
We investigate electronic band-structure images in reciprocal space of few layer graphene epitaxially grown on SiC(000-1). In addition to the observation of commensurate rotation angles of the graphene layers, the k-space images recorded…
We use angle-resolved photoemission spectroscopy to investigate the electronic structure of bilayer graphene at high n-doping and extreme displacement fields, created by intercalating epitaxial monolayer graphene on silicon carbide with…
On the basis of self-consistent Born approximation for Dirac fermions under charged impurity scatterings in graphene, the theory for calculating the thermo-electric power is developed by using the heat current-current correlation function.…
The electromagnetic response of graphene, expressed by the dielectric function, and the spectrum of collective excitations are studied as a function of wave vector and frequency. Our calculation is based on the full band structure,…
We modulate the atomic structure of bilayer graphene by driving its lattice at resonance with the in-plane E1u lattice vibration at 6.3um. Using time- and angle-resolved photoemission spectroscopy (tr-ARPES) with extreme ultra-violet (XUV)…
The electromagnetic response of Dirac semimetals in the infrared and terahertz frequency ranges is attracting growing interest for potential applications in optoelectronics and nonlinear optics. The interplay between the free-carrier…
We have measured the electrical response to NO$_2$, N$_2$, NH$_3$ and CO for epitaxial graphene and quasi freestanding epitaxial graphene on 6H-SiC substrates. Quasi freestanding epitaxial graphene shows a 6 fold increase in NO2 sensitivity…
We present an electron projection imaging method to study the ultrafast evolution of photoelectron density distribution and transient fields near the surface. The dynamical profile of the photoelectrons from graphite reveals an origin of a…
We predict that graphene is a unique system where disorder-assisted scattering (supercollisions) dominates electron-lattice cooling over a wide range of temperatures, up to room temperature. This is so because for momentum-conserving…
The thermoelectric response of high mobility single layer epitaxial graphene on silicon carbide substrates as a function of temperature and magnetic field have been investigated. For the temperature dependence of the thermopower, a strong…