Related papers: Seed source for plasma compression in the long wav…
Ultrashort long-wave infrared (LWIR) laser pulses can resonantly excite vibrations in N2 and O2 through a two-photon transition. The absorptive, vibrational component of the ultrafast optical nonlinearity grows in time, starting smaller…
The paper presents a study of wakefield generation and electron injection via propagation of radially polarized laser pulses in homogeneous pre-ionized plasma. The analytical study is based on Lorentz force and continuity equations.…
We experimentally and theoretically investigate the process of seeded intermodal four-wave mixing in a graded index multimode fiber, pumped in the normal dispersion regime. By using a fiber with a 100 micron core diameter, we generate a…
Creating extended, highly homogeneous plasma columns like that required by plasma wakefield accelerators can be a challenge. We study the propagation of ultra-short, TW power ionizing laser pulses in a 10-meter-long rubidium vapor and the…
We present experimental evidence supported by simulations of a relativistic ionization wave launched into surrounding gas by the sheath field of a plasma filament with high energy electrons. Such filament is created by irradiating a…
In the frame of laser-driven wakefield acceleration, the main characteristics oflaser propagation and plasma wave excitation are described, with an emphasis onthe role of propagation distance for electron acceleration. To…
Properties of filaments ignited by multi-millijoule, 90-fs mid-IR pulses centered at 3.9 {\mu}m are examined experimentally by monitoring plasma density and losses as well as spectral dynamics and beam profile evolution at different…
It is well known that optical emission produced by femtosecond laser-induced breakdown on a surface may be enhanced by using a pair of laser pulses separated by a suitable delay. Here we elucidate the mechanism for this effect both…
A novel method is presented for generating radiation using the beat wave associated with a bi-frequency laser pulse, to excite plasma oscillations in a plasma slab with a density gradient. By resonantly exciting a plasma wave, it can be…
Recent experiments have shown that femtosecond filamentation plasmas generate ultra-broadband radio frequency radiation (RF). We show that a combination of plasma dynamics is responsible for the RF: a plasma wake field develops behind the…
Infrared femtosecond laser pulses are important tools both in strong-field physics, driving X-ray high-harmonic generation, and as the basis for widely tuneable, if inefficient, ultrafast sources in the visible and ultraviolet. Although…
We demonstrate an efficient scheme for the generation of broadband, high-energy, circularly polarized femtosecond laser pulses in the deep ultraviolet through seeded degenerate four-wave mixing in stretched gas-filled hollow capillary…
We present the generation of THz radiation by focusing ultrafast laser pulses with three incommensurate wavelengths to form a plasma. The three colors include 800 nm and the variable IR signal and idler outputs from an optical parametric…
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…
We propose a new method for laser pulse compression that uses the spatially varying dispersion of a plasma plume with a density gradient. This novel scheme can be used to compress ultrahigh power lasers. A long, negatively…
An emission tomography of laser-induced plasmas employed in the laser induced breakdown spectroscopy (LIBS) requires long signal integration times during which the plasma cannot be considered stationary. To reduce the integration time, it…
In plasma-based backward Raman amplifiers, the output pulse intensity increases with the input pump pulse intensity, as long as the Langmuir wave mediating energy transfer from the pump to the seed pulse remains intact. However, at high…
This chapter starts with a discussion of the main qualitative differences between UV and mid-IR filaments: from multiphoton ionization in the UV to tunnel ionization in the near- to mid-IR. A general qualitative analysis of the properties…
We show the feasibility of generating X-ray pulses in the 4 to 8 keV fundamental photon energy range with 0.65 TW peak power, 15 fs pulse duration, $9\times10^{-5}$ bandwidth, using the LCLS-II copper linac and hard X-ray (HXR) undulator.…
We consider the generation of a quasistatic longitudinal electric field by intense laser pulses propagating in a transparent plasma with radiation friction taken into account. For both circular and linear polarization of the driving pulse…