English
Related papers

Related papers: A Study on Angular Distribution of THz Radiation D…

200 papers

Photoionization by a femtosecond, terawatt laser pulse generates a plasma column in a neutral ambient gas. Velocity of electrons, pushed by the laser ponderomotive force along the column surface, couples to the the radial density gradient…

Plasma Physics · Physics 2020-09-29 S. Y. Kalmykov , A. Englesbe , J. Elle , A. Schmitt-Sody

Speckle patterns observed in coherent optical imaging reflect important characteristic information of the scattering object. To capture speckle patterns, angular resolved or oblique illumination geometries are usually employed in…

Optics · Physics 2023-02-22 Kuangyi Xu , Zachery B. Harris , M. Hassan Arbab

The polarization states of terahertz (THz) radiation generated in a photo-ionized gas driven by strong two- or multi-frequency fields with locally controlled polarization are studied. We reveal a universal property of the resulting THz…

High-order harmonic generation in the presence of a chirped THz pulse is investigated numerically with a complete 3D non-adiabatic model. The assisting THz pulse illuminates the HHG gas cell laterally inducing quasi-phase-matching. We…

We investigate a two-level atom in the field of a strong laser pulse. The resulting time-dependent polarization is the source of a radiation the frequency components of which are essentially harmonics of the driving field's carrier…

Quantum Physics · Physics 2016-09-13 Ákos Gombkötő , Attila Czirják , Sándor Varró , Péter Földi

We study the generation of terahertz radiation from atoms and molecules driven by an ultrashort fundamental laser and its second harmonic field by solving time-dependent Schr\"odinger equation (TDSE). The comparisons between one-, two-, and…

On the basis of a quantum microscopic approach we study the dynamics of the afterglow of a dilute Gaussian atomic ensemble excited by pulsed radiation. Taking into account the vector nature of the electromagnetic field we analyze in detail…

Quantum Physics · Physics 2017-08-23 A. S. Kuraptsev , I. M. Sokolov , M. D. Havey

The availability of few-cycle optical pulses opens a window to physical phenomena occurring on the attosecond time scale. In order to take full advantage of such pulses, it is crucial to measure and stabilise their carrier-envelope (CE)…

We demonstrate photoacoustic wave propagation with a plane wavefront in liquid water using a terahertz (THz) laser pulse. The THz light can effectively generate the photoacoustic wave in water because of strong absorption via a stretching…

Optics · Physics 2020-08-20 Masaaki Tsubouchi , Hiromichi Hoshina , Masaya Nagai , Goro Isoyama

We study the penetration of ultraintense circularly polarized laser pulses into a thick subcritical plasma layer with accounting for radiation friction. We show that radiation pressure is enhanced by radiation friction in the direction…

Plasma Physics · Physics 2017-12-04 E. G. Gelfer , N. V. Elkina , A. M. Fedotov

We present a temporally-multiplexed dual-colour terahertz (THz) imaging technique using THz-to-optical conversion in atomic vapour. By rapidly alternating the pump laser frequency, we sequentially excite two atomic states, each absorbing a…

Atomic Physics · Physics 2025-07-16 Lucy A. Downes , C. Stuart Adams , Kevin J. Weatherill

Using high-resolution, two-dimensional particle-in-cell simulations, we investigate numerically the mechanisms of terahertz (THz) emissions in submicron-thick carbon solid foils driven by ultraintense ($\sim 10^{20}\,\rm W\,cm^{-2}$),…

Plasma Physics · Physics 2020-07-10 J. Déchard , X. Davoine , L. Gremillet , L. Bergé

Broadband ultrashort terahertz (THz) pulses can be produced using plasma generation in a noble gas ionized by femtosecond two-color pulses. Here we demonstrate that, by using multiple-frequency laser pulses, one can obtain a waveform which…

We study nondipole effects in multiphoton ionization of a two-dimensional hydrogen-like atom by a flat-top laser pulse of varied intensity. For this purpose, we solve numerically a two-dimensional Schr\"odinger equation treating a…

Atomic Physics · Physics 2024-12-25 J. Z. Kamiński , K. Krajewska

We consider the effect of spatial correlations on sources of polarized electromagnetic radiation. The sources, assumed to be monochromatic, are constructed out of dipoles aligned along a line such that their orientation is correlated with…

Optics · Physics 2007-05-23 Abhishek Agarwal , Pankaj Jain , Jagdish Rai

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…

Pulsed terahertz (THz) radiation, generated through optical rectification (OR) by exciting [110] ZnTe crystal with ultrafast optical pulses, typically consists of only a few cycles of electromagnetic field oscillations with a duration about…

We show that for an observer in translational, rotational or gravitational motion, a linearly polarized plane wave has two modes of propagation in a stationary, homogeneous and isotropic medium according to Hertz's version of Maxwell's…

General Physics · Physics 2007-05-23 A. I. A. Adewole

Until recently, theoretical and experimental studies of photoelectron angular distributions (PADs) including non-dipole effects in atomic photo\-ionization have been performed mainly for the conventional plane-wave radiation. One can…

Atomic Physics · Physics 2023-08-21 Maksim D. Kiselev , Elena V. Gryzlova , Alexei N. Grum-Grzhimailo

High-energy terahertz pulses are challenging to produce due to the low conversion efficiency and limited optical damage threshold of nonlinear crystals. Here, we describe the high-efficiency generation of terahertz radiation pulses with…

Plasma Physics · Physics 2026-04-22 Sida Cao , Matthew R. Edwards