Related papers: Interface defect-assisted phonon scattering of hot…
Controlling energy flows in solids through switchable electron-lattice cooling can grant access to a range of interesting and potentially useful energy transport phenomena. Here we discuss a unique switchable electron-lattice cooling…
Using optical-pump terahertz-probe spectroscopy, we study the relaxation dynamics of photoexcited carriers in graphene at different temperatures. We find that at lower temperatures the tail of the relaxation transients as measured by the…
We perform a femtosecond-THz optical pump-probe spectroscopy to investigate the cooling dynamics of hot carriers in quasi-free standing bilayer epitaxial graphene. We observed longer decay time constants, in the range of 2.6 to 6.4 ps,…
Time dynamics of photoexcited electron-hole pairs is important for a number of technologies, in particular solar cells. We combined ultrafast pump-probe Raman scattering and photoemission to directly follow electron-hole excitations as well…
Ultrafast electron-phonon relaxation dynamics in graphene hides many distinct phenomena, such as hot phonon generation, dynamical Kohn anomalies, and phonon decoupling, yet still remains largely unexplored. Here, we unravel intricate…
Using electrical transport experiments and shot noise thermometry, we find strong evidence that "supercollision" scattering processes by flexural modes are the dominant electron-phonon energy transfer mechanism in high-quality, suspended…
We examine the photoconductivity of an intrinsic graphene associated with far- and mid-infrared irradiation at low temperatures. The model under consideration accounts for the excitation of the electron-hole pairs by incident radiation, the…
Evidence is accumulating for the crucial role of a solid's free electrons in the dynamics of solid-liquid interfaces. Liquids induce electronic polarization and drive electric currents as they flow; electronic excitations, in turn,…
We report on the temperature dependent electron transport in graphene at different carrier densities $n$. Employing an electrolytic gate, we demonstrate that $n$ can be adjusted up to 4$\times10^{14}$cm$^{-2}$ for both electrons and holes.…
The Dirac dispersion of graphene limits the phase space available for energy transport between electrons and acoustic phonons at temperatures above the Bloch-Grueneisen temperature. Consequently, energy transport can be dominated by…
Carrier relaxation measurements in moir\'e materials offer a unique probe of the microscopic interactions, in particular the ones that are not easily measured by transport. Umklapp scattering between phonons is a ubiquitous…
Graphene is emerging as a viable alternative to conventional optoelectronic, plasmonic, and nanophotonic materials. The interaction of light with carriers creates an out-of-equilibrium distribution, which relaxes on an ultrafast timescale…
We present an ab-initio study of photocarrier dynamics in graphene due to electron-phonon (EP) interactions. Using the Boltzmann relaxation-time approximation with parameters determined from density functional theory (DFT) and a…
Since the first graphene layer was fabricated in the early 2000's, graphene properties have been studied extensively both experimentally and theoretically. However, when comparing the many resistivity models reported in literature, several…
We investigate the energy relaxation of hot carriers produced by photoexcitation of graphene through coupling to both intrinsic and remote (substrate) surface polar phonons using the Boltzmann equation approach. We find that the energy…
Ultrafast thermal transport in low-dimensional materials challenges traditional diffusive models due to reduced scattering, strong electron-phonon coupling, and pronounced non-equilibrium effects. To address these complexities, we extend…
We present a first-principles study of the temperature- and density-dependent intrinsic electrical resistivity of graphene. We use density-functional theory and density-functional perturbation theory together with very accurate Wannier…
Ultrafast dynamics of graphite is investigated by time-resolved photoemission spectroscopy. We observe spectral features of direct photoexcitations, non-thermal electron distributions, and recovery dynamics occurring with two time scales…
In nearly compensated graphene, disorder-assisted electron-phonon scattering or "supercollisions" are responsible for both quasiparticle recombination and energy relaxation. Within the hydrodynamic approach, these processes contribute weak…
A discovery of the unusual thermal properties of graphene stimulated experimental, theoretical and computational research directed at understanding phonon transport and thermal conduction in two-dimensional material systems. We provide a…