Femtosecond laser-produced plasmas are bright ultrafast line x-ray sources potentially suitable for different applications including material science and biology. The conversion efficiency of the laser energy incident onto a solid target into the x-ray emission is significantly enhanced when a laser prepulse precedes the main pulse. The details of x-ray line emission from solid targets irradiat...

Single-color illumination of a copper surface by a red or an ultraviolet femtosecond laser pulse yields a threephoton (red) or a two-photon (UV) photoemission process. A multicolor, multiphoton process is generated when the red and the UV pulses overlap both in space and in time on the photocathode. It is shown that this emission process results from the absorption by an electron of one red and...

The carrier-envelope phase slip of an ultrashort pulse circulating in a mode-locked Ti:sapphire laser is analyzed. The laser cavity is modeled by a dispersion- and nonlinearity-managed nonlinear Schrödinger equation. The combined contributions to the phase slip induced by nonlinear phase and nonlinear dispersion are found to approach zero for strong dispersion maps. The dependence of the slip o...

ABSTRACT Thin films of indocyanine green J-aggregates in polymers have been prepared and their saturable absorption properties studied in a high intensity regime using a unique ultrashort pulse Ti:sapphire laser (10 fs) with a very broad bandwidth (over 200 nm at −20 dB). The samples showed a surprisingly high stability to irradiation, strong absorption bleaching, and wavelength dependent diffe...

The description of ultrashort laser pulse filamentation in condensed media as a spontaneous formation of X waves is shown to apply also to filaments generated in air. Within this framework, a simple explanation is brought for several features of the filament such as the subdiffractive propagation and the energy flux from the weakly localized tails of the X-waves to the intense core.

Radiation-reaction effects in the interaction of an electron bunch with a superstrong focused ultrashort laser pulse are investigated in the quantum radiation-dominated regime. The angle-resolved Compton scattering spectra are calculated in laser pulses of variable duration using a semiclassical description for the radiation-dominated dynamics and a full quantum treatment for the emitted radiat...