相关论文: Soft pair excitations and double-log divergences d…
The conversion of light into free electron-hole pairs constitutes the key process in the fields of photodetection and photovoltaics. The efficiency of this process depends on the competition of different relaxation pathways and can be…
Photo-excitation in solids can trigger a cascade in which multiple particle-hole excitations are generated. We analyze the carrier multiplication cascade of impact excitation processes in graphene and show that the number of pair…
According to quantum electrodynamics (QED), a strong external field can make the vacuum state decay producing electron-positron pairs. Here we investigate emission of soft photons which accompanies a nonperturbative process of pair…
The QED cascade induced by the two counter-propagating lasers is studied. It is demonstrated that the probability of a seed-photon to create a pair is much larger than that of a seed-electron. By analyzing the dynamic characteristics of the…
The diffusion of electron-hole pairs, which are excited in an intrinsic graphene by the ultrashort focused laser pulse in mid-IR or visible spectral region, is described for the cases of peak-like or spread over the passive region…
The tight-binding model is closely associated with the modified layer-based random-phase approximation to thoroughly investigate the electron-electron interactions in sliding bilayer graphene. The Coulomb interactions and intralayer and…
The density of electron-hole pairs produced in a graphene sample immersed in a homogeneous time-dependent electrical field is evaluated. Because low energy charge carriers in graphene are described by relativistic quantum mechanics, the…
We discuss the production of soft photons in high energy hadron-hadron collisions. We present a model where quarks and antiquarks in the hadrons emit ``synchrotron light'' when being deflected by the chromomagnetic fields of the QCD vacuum,…
Generation of quasi-particle--hole pairs in gapped graphene monolayers in the combined field of two counterpropagating light waves is studied. The process represents an analogue of electron-positron pair production from the QED vacuum by…
We explore the relaxation of photo-excited graphene by solving a transient Boltzmann transport equation with electron-phonon (e-ph) and electron-electron (e-e) scattering. Simulations show that when the excited carriers are relaxed by e-ph…
High-harmonic generation (HHG) is a coherent optical process in which the incident photon energy is up-converted to the multiples of its initial energy. In solids, under the influence of a strong laser field, electron-hole (e-h) pairs are…
We report a theoretical study of the many-body effects of electron-electron interaction on the ground-state and spectral properties of double-layer graphene. Using a projector-based renormalization method we show that if a finite voltage…
In Dirac materials linear band dispersion blocks momentum-conserving interband transitions, creating a bottleneck for electron-hole pair production and carrier multiplication in the photoexcitation cascade. Here we show that the decays are…
The process of coherent creation of particle - hole excitations by an electric field in graphene is quantitatively described using a dynamic "first quantized" approach. We calculate the evolution of current density, number of pairs and…
High harmonic generation (HHG) in solids reflects the underlying nonperturbative nonlinear dynamics of electrons in a strong light field and is a powerful tool for ultrafast spectroscopy of electronic structures. Photo-carrier doping allows…
We investigate the signature of the low-energy electronic excitations in the Raman spectrum of monolayer and bilayer graphenes. The dominant contribution to the Raman spectra is due to the interband electron-hole pairs, which belong to the…
The electron-hole liquid, which features a macroscopic population of correlated electrons and holes, may offer a path to room temperature semiconductor devices that harness collective electronic phenomena. We report on the gas-to-liquid…
The momentum distributions of electron-hole (EH) pair production in graphene for two arbitrarily polarized electric fields with a time delay are investigated employing a massless quantum kinetic equation and compared with the results…
A theory of shake-up processes in photoabsorption of an interacting low-density two-dimensional electron gas (2DEG) in strong magnetic fields is presented. In these processes, an incident photon creates an electron-hole pair and, because of…
The interaction of high energy electrons, positrons, and photons with intense laser pulses is studied in head-on collision geometry. It is shown that electrons and/or positrons undergo a cascade-type process involving multiple emissions of…