Related papers: CEP-stable Tunable THz-Emission Originating from L…
We have measured electron energy distribution curves (EDCs) of the laser-induced field emission from a tungsten tip. Field emission from photo-excited nonequilibrium electron distributions were clearly observed, while no enhanced field…
We show that a field emission tip electron source that is triggered with a femtosecond laser pulse can generate electron pulses shorter than the laser pulse duration (~100 fs). The emission process is sensitive to a power law of the laser…
Precise control of the electron phase accumulated during its sub-cycle motion within intense laser fields is essential in strong-field physics, yet remains mostly indirect and complicated so far. In this Letter, we develop a novel approach…
We show that coherently driven atomic or molecular media potentially yield strong controllable short pulses of THz radiation. The method is based on excitation of maximal quantum coherence in a gas medium by optical pulses and coherent…
We investigate spontaneous radiative processes in a driven polar two-level system whose interaction with the laser field is dominated by broken inversion symmetry rather than by the usual transition dipole coupling. Using a polaron…
The generation of stable trains of ultra-short (fs-ps), terahertz (THz)-frequency radiation pulses, with large instantaneous intensities, is an underpinning requirement for the investigation of light-matter interactions, for metrology and…
We develop a theoretical model for a tunable coherent terahertz radiation source based on the long-lived Bose condensate of photons. In the device we propose, the original photon pumping is performed incoherently by a blackbody radiation…
Terahertz (THz) radiation, spanning from 0.3 to 3x10^12 Hz, fills the crucial gap between the microwave and infrared spectral range. THz technology has found applications in various fields, from imaging and sensing to telecommunication and…
We construct a terahertz time-domain spectrometer (THz-TDS) system based on photoconductive antenna (PCA). A 800 nm Ti sapphire femtosecond laser with 80 MHz repetition rate provides the pump and probe laser pulse, which has a 45 fs pulse…
We propose a scheme for generation of continuous-wave THz radiation. The scheme requires a medium where three discrete states in a $\Lambda $ configuration can be selected, with the THz-frequency transition between the two lower metastable…
The growing requirements of pump-probe techniques and nonlinear optics experiments greatly promote the studies of two-color free-electron lasers (FELs). We propose a new method to generate coherent two-color pulses in a high-gain harmonic…
This is a brief overview of the main physical ideas for application of field effect transistors for generation and detection of TeraHertz radiation. Resonant frequencies of the two-dimensional plasma oscillations in FETs increase with the…
In this paper, electromagnetic emissions produced in a thin beam-plasma system are studied using two-dimensional particle-in-cell simulations. For the first time, the problem of emission generation in such a system is considered in the…
We demonstrate the self-phase modulation (SPM) of a single-cycle THz pulse in a semiconductor, using bulk n-GaAs as a model system. The SPM arises from the heating of free electrons in the electric field of the THz pulse, leading to an…
We present a proposal for a tunable source of single photons operating in the terahertz (THz) regime. This scheme transforms incident visible photons into quantum THz radiation by driving a single polar quantum emitter with an optical…
Electron-beams with a sinusoidal energy modulation have the potential to emit sub-femtosecond x-ray pulses in a free-electron laser. The energy modulation can be generated by overlapping a powerful infrared laser with an electron-beam in a…
Turbulence is a predominant process for energizing electrons and ions in collisionless astrophysical plasmas, and thus is responsible for shaping their radiative signatures (luminosity, spectra, and variability). To better understand the…
A compact accelerator based super-radiant THz source is under development at Inter University Accelerator Centre (IUAC), New Delhi. The facility is based on the principle of pre-bunched Free Electron Laser (FEL) which will produce THz…
In the present study, the generation of THz radiation through wakefield excitation in a cylindrical dielectric plasma waveguide is investigated. The proposed hybrid dielectric-plasma wakefield structure combines the advantages of dielectric…
We report THz-pump / mid-infrared probe near-field studies on Si-doped GaAs-InGaAs core-shell nanowires utilizing THz radiation from the free-electron laser FELBE. Upon THz excitation of free carriers, we observe a red shift of the plasma…