相关论文: Ultrafast pseudospin dynamics in graphene
The ability to manipulate electrons with the intense laser pulse enables an unprecedented control over the electronic motion on its intrinsic timescale. Present work explores the desired control of photocurrent generation in monolayer…
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…
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…
In recent years, phonon electron carrier dragging has emerged as an innovative approach for modulating energy transfer in low dimensional systems. In this Letter, we explore the fundamental mechanisms of electron-phonon coupling and the…
A fourteen-fold anisotropy in the spin transport efficiency parallel and perpendicular to the charge transport is observed in a vertically-biased (Ga,Mn)As-based spin-polarized light emitting diode. The spin polarization is determined by…
Hot electron effects in graphene are significant because of graphene's small electronic heat capacity and weak electron-phonon coupling, yet the dynamics and cooling mechanisms of hot electrons in graphene are not completely understood. We…
The broadband and ultrafast photoresponse of graphene has been extensively studied in recent years, although the photoexcited carrier dynamics is still far from being completely understood. Different experimental approaches imply either one…
The electronic properties of graphene are unique and are attracting increased attention to this novel 2-dimensional system. Its photonic properties are not less impressive. For example, this single atomic layer absorbs through direct…
The equilibrium optical phonons of graphene are well characterized in terms of anharmonicity and electron-phonon interactions, however their non-equilibrium properties in the presence of hot charge carriers are still not fully explored.…
Black phosphorus is emerging as a promising semiconductor for electronic and optoelectronic applications. To study fundamental carrier properties, we performed ultrafast femtosecond pump-probe spectroscopy on thin film black phosphorus…
We investigate the dynamics of photoexcited carriers and nonequilibrium phonons in graphene by solving the microscopic kinetic Bloch equations. The pump and drift effects from the laser field as well as the relevant scatterings (including…
Phosphorene, an emerging elemental two-dimensional (2D) direct band gap semiconductor with fascinating structural and electronic properties distinctively different from other 2D materials such as graphene and MoS2, is promising for novel…
Inelastic phonon scattering in graphene field-effect transistors (FETs) is studied by numerically solving the Boltzmann transport equation in three dimensional real and phase spaces (x, kx, ky). A kink behavior due to ambipolar transport…
A far-reaching goal of graphene research is exploiting the unique properties of carriers to realize extreme nonclassical electronic transport. Of particular interest is harnessing wavelike carriers to guide and direct them on submicron…
Photonic metasurfaces are ultrathin electromagnetic wave-molding metamaterials providing the missing link for the integration of nanophotonic chips with nanoelectronic circuits. An extra twist in this field originates from spin-optical…
We demonstrate anisotropic photostriction in two-dimensional orthorhombic semiconductors using time-dependent density functional theory. By tracing the dynamics of photoexcited carriers, we establish a quantitative link between carrier…
Identifying the microscopic nature of non-equilibrium energy transfer mechanisms among electronic, spin and lattice degrees of freedom is central for understanding ultrafast phenomena such as manipulating magnetism on the femtosecond…
We present perturbative analytical results of the Landau level quasienergy spectrum, autocorrelation function and out of plane pseudospin polarization for a single graphene sheet subject to intense circularly polarized terahertz radiation.…
At the 2D limit, hexagonal systems such as monolayer transition metal dichalcogenides (TMDs) and graphene exhibit unique coupled spin and momentum-valley physics (valley pseudospin) owing to broken spatial inversion symmetry and strong…
As an emerging single elemental layered material with a low symmetry in-plane crystal lattice, black phosphorus (BP) has attracted significant research interest owing to its unique electronic and optoelectronic properties, including its…