Related papers: Mapping the power-law decay of high-harmonic spect…
We report the enhancement of individual harmonics generated at a relativistic ultra-steep plasma vacuum interface. Simulations show the harmonic emission to be due to the coupled action of two high velocity oscillations -- at the…
We model the emission of high energy photons due to relativistic charged particle motion in intense laser-plasma interactions. This is done within a particle-in-cell code, for which high frequency radiation normally cannot be resolved due…
Ever since the advent of high-order harmonic generation, one of the main goals has been to maximize the high harmonic yield. This is due to the wide range of applications in multidisciplinary research fields, including nonlinear XUV optics…
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…
When a high-contrast ultra-relativistic laser beam enters a micro-sized plasma waveguide, the pulse energy is coupled into waveguide modes, which remarkably modifies the interaction of electrons and electromagnetic wave. The electrons that…
An intense X wave propagating perpendicularly to dc magnetic field is unstable with respect to a parametric decay into an electron Bernstein wave and a lower-hybrid wave. A modified theory of this effect is proposed that extends to the…
Type-III-burst radio signals can be mimicked in the laboratory via laser-plasma interaction. Instead of an electron beam generating Langmuir waves (LW) in the interplanetary medium, the LWs are created by a laser interacting with a…
The mechanism of harmonic generation in both O and X-mode configurations for a magnetized plasma has been explored here in detail with the help of Particle-In-Cell (PIC) simulations. A detailed characterization of both the reflected and…
Pulse shaping provides a significant level of control and precision when optimizing laser-plasma interactions. Pulse shaping enables precise control and manipulation, resulting in enhanced energy deposition, optimized particle acceleration,…
The physics governing electron acceleration by a relativistically intense laser are not confined to the critical density surface, they also pervade the sub-critical plasma in front of the target. Here, particles can gain many times the…
Using fully kinetic simulations, we demonstrate that magnetic reconnection in relativistic plasmas is highly efficient at accelerating particles through a first-order Fermi process resulting from the curvature drift of particles in the…
We demonstrate a new high-order harmonic generation mechanism reaching the `water window' spectral region in experiments with multi-terawatt femtosecond lasers irradiating gas jets. A few hundred harmonic orders are resolved, giving uJ/sr…
Waveform shaping and frequency synthesis based on waveform modulation is ubiquitous in electronics, telecommunication technology, and optics. For optical waveforms, the carrier frequency is on the order of several hundred THz, while the…
Heating and ionization are among the most fundamental processes in relativistic laser--solid interactions; however, their spatiotemporal evolution remains challenging to capture experimentally. Here we present detailed diagnosis of…
We study the permanent regimes of the reduced Vlasov-Maxwell system for laser-plasma interaction. A non-relativistic and two different relativistic models are investigated. We prove the existence of solutions where the distribution function…
In this article, we derive analytically the complex optical spectrum of a pulsed laser source obtained when a frequency comb generated by phase modulation is input into a synchronized intensity modulator. We then show how this knowledge of…
When a high power laser beam irradiates a small aperture on a solid foil target, the strong laser field drives surface plasma oscillation at the periphery of this aperture, which acts as a "relativistic oscillating window". The diffracted…
We show how bright, fully coherent, hard x-ray beams can be generated through nonlinear upconversion of femtosecond laser light. By using longer-wavelength mid-infrared driving lasers of moderate peak intensity, full phase matching of the…
Photons that decouple from a relativistic jet do so over a range of radii, which leads to a spreading in arrival times at the observer. Therefore, changes to the comoving photon distribution across the decoupling zone are encoded in the…
A high energy power law is a common feature in the spectra of many astrophysical objects. We show that the photons in a relativistic plasma with a variable Lorentz factor go through repeated scattering with electrons to gain energy. The…