相关论文: Spatial separation of large dynamical blue shift a…
We present a combined theoretical and experimental study of spatio-temporal propagation effects in terahertz (THz) generation in gases using two-color ionizing laser pulses. The observed strong broadening of the THz spectra with increasing…
Plasma high harmonics generation from an extremely intense short-pulse laser is explored by including the effects of ion motion, electron-ion collisions and radiation reaction force in the plasma dynamics. The laser radiation pressure…
We apply the theory of high-order harmonic generation by low-frequency laser fields in the strong field approximation to the study of the spatial and temporal coherence properties of the harmonics. We discuss the role of dynamically induced…
The production of brighter coherent XUV radiation by intense laser pulses through the process of high-harmonic generation (HHG) is a central challenge in contemporary nonlinear optics. We study the generation and spatial propagation of high…
We report a systematic investigation into the processes behind a near hundredfold enhanced second harmonic wave generated from a laser-induced air plasma, by examining the temporal dynamics of the frequency conversion processes, and the…
We present a classical model for high harmonic generation during the propagation of an intense laser pulse through an atomic gas. Numerical simulations of the model show excellent quantitative agreement with the corresponding quantum model…
High-harmonic generation is one of the most extreme nonlinear-optical processes observed to date. By focusing an intense laser pulse into a gas, the light-atom interaction that occurs during the process of ionising the atoms results in the…
The generation of harmonics by atoms interacting with two circularly polarized and frequency related laser fields is addressed through ab initio numerical simulations. A detailed charaterization of a few specific harmonics is given. In…
The harmonic emission from cluster nanoplasmas subject to short, intense infrared laser pulses is analyzed by means of particle-in-cell simulations. A pronounced resonant enhancement of the low-order harmonic yields is found when the Mie…
High harmonic generation in benzene is studied using a mixed quantum-classical approach in which the electrons are described using time-dependent density functional theory while the ions move classically. The interaction with both…
We discuss harmonic generation in the case of laser field-dressed Hamiltonians that are invariant under so-called dynamical symmetry operations. Examples for such systems are molecules which exhibit a discrete rotational symmetry of order N…
When a laser pulse impinges on a molecule which is invariant under certain symmetry operations selection rules for harmonic generation (HG) arise. In other words: symmetry controls which channels are open for the deposition and emission of…
We photoionize laser-cooled atoms with a laser beam possessing spatially periodic intensity modulations to create ultracold neutral plasmas with controlled density perturbations. Laser-induced fluorescence imaging reveals that the density…
The generation of high-order harmonics in bulk solids subjected to intense ultrashort laser pulses has opened up new avenues for research in extreme nonlinear optics and light-matter interaction on sub-cycle timescales. Despite significant…
The laser interaction with an electron-positron-ion mixed plasma is studied, from the perspective of the associated high-order harmonic generation. For an idealized mixed plasma which is assumed with a sharp plasma-vacuum interface and…
We study numerically the interaction between an intense circularly polarized laser field and an electron moving in a potential which has a discrete cylindrical symmetry with respect to the laser pulse propagation direction. This setup…
This work theoretically investigates high-order harmonic generation in rare gas atoms driven by two temporally delayed ultrashort laser pulses. Apart from their temporal delay, the two pulses are identical. Using a single-atom model of the…
Optical techniques for spatiotemporal control can produce laser pulses with custom amplitude, phase, or polarization structure. In nonlinear optics and plasma physics, the use of structured pulses typically follows a forward design…
High-order harmonic generation via single-slit diffraction of relativistic laser pulses is investigated. Using fully kinetic 2D and 3D particle-in-cell simulations, we show that interesting optical phenomena emerge, including the generation…
Although the frequency shift and odd-even intensity modulation in high-order harmonic generation (HHG) have both been observed for asymmetric laser-target systems, they are typically studied as two separate phenomena. In this Letter, we…