相关论文: Laser-Induced Above-Bandgap Transparency in GaAs

In (100)-oriented GaAs illuminated at normal incidence by a laser and its second harmonic, interference between one- and two-photon absorption results in ballistic current injection, but not modulation of the overall carrier injection rate.…

We present ab initio quasiparticle self-energy calculations in crystalline GaAs for cases of intense electronic excitation (~ 10% of valence electrons excited into conduction band), relevant for high-intensity ultra-short pulsed laser…

The phenomenon of a dispersion bandgap opening between low-loss spectral windows of odd and even plasmonic modes in a layered insulator-metal-insulator plasmonic waveguide is introduced. Beginning with a three layer plasmonic dispersion…

We measure fast carrier decay rates (6 ps) in GaAs photonic crystal cavities with resonances near the GaAs bandgap energy at room temperature using a pump-probe measurement. Carriers generated via photoexcitation using an above-band…

Could a laser field lead to the much sought-after tunable bandgaps in graphene? By using Floquet theory combined with Green's functions techniques, we predict that a laser field in the mid-infrared range can produce observable bandgaps in…

We report on experimental and theoretical study of the nonlinear Faraday effect under conditions of electromagnetically induced transparency at the 5$S_{1/2} \to 5P_{3/2} \to 5D_{5/2}$ two-photon transition in rubidium vapors. These…

Electromagnetically-induced transparency has become an important tool to control the optical properties of dense media. However, in a broad class of systems, the interplay between inhomogeneous broadening and the existence of several…

We predict a strong-field ultrafast optical Faraday effect, where a circularly polarized ultrashort optical pulse induces transient chirality in an achiral transparent dielectric. This effect is attractive for time-resolved measurements…

It is shown that the well-known blue-shift of the fundamental absorption edge in as-deposited compositionally modulated amorphous Si/Ge and As6Se94/Se80Te20 multilayers (with periods of 4-8 nm) is further enhanced due to the thermal or…

A gain-assisted plasmonic waveguide with two detuned resonators is investigated in the plasmon-induced transparency window. Phase map is employed to study power transmittance and group delay for varying gain coefficients and frequency…

We report on the first results of laser plasma wakefield acceleration driven by ultrashort mid-infrared laser pulses (\lambda= 3.9 \mu m, 100 fs, 0.25 TW), which enable near- and above-critical density interactions with moderate-density gas…

Laser induced line narrowing effect, discovered more than thirty years ago, can also be applied to recent studies in high resolution spectroscopy based on electromagnetically induced transparency. In this paper we first present a general…

The speed of ultra-fast optical switches is generally limited by the intrinsic electronic response time of the material. Here we show that the phase content of selected electromagnetic pulses can be used to measure the timescales…

We present an optical conductivity study of the multifold semimetal PdGa, performed in a broad spectral range (100 - 20000 cm-1; 12 meV - 2.5 eV) down to T = 10 K. The conductivity at frequencies below 4000 cm-1 is dominated by free…

Optomechanical systems have been shown both theoretically and experimentally to exhibit an analogon to atomic electromagnetically induced transparency, with sharp transmission features that are controlled by a second laser beam. Here we…

We report high-pressure photoluminescence, Raman scattering, and x-ray diffraction measurements on a lead-free halide perovskite $Cs_3Sb_2Br_9$. At about 3 GPa, an electronic transition manifests itself through a broad minimum in linewidth,…

In this article, we report the first observation of nanosecond laser induced transient dual absorption bands, one in the bandgap (TA1) and another in the sub-bandgap (TA2) regions of a-Ge5As30Se65 thin films. Strikingly, these bands are…

Bosonic cascade lasers are terahertz (THz) lasers based on stimulated radiative transitions between bosonic condensates of excitons or exciton-polaritons confined in a trap. We study the interaction of an incoming THz pulse resonant in…

We experimentally demonstrate at terahertz frequencies that a planar metamaterial exhibits a spectral response resembling electromagnetically induced transparency. The metamaterial unit cell consists of a split ring surrounded by another…

Interband transitions of electrons in a gapped graphene monolayer are highly stimulated near the Fermi surface when a high-frequency electric wave of weak intensity and a strong constant electric field are superposed in the plane of the…