Intense isolated attosecond pulses from two-color few-cycle laser driven relativistic surface plasma

Abstract

Ultrafast plasma dynamics play a pivotal role in the relativistic high harmonic generation, a phenomenon that can give rise to intense light fields of attosecond duration. Controlling such plasma dynamics holds key to optimize the relevant sub-cycle processes in the high-intensity regime. Here, we demonstrate that the optimal coherent combination of two intense ultrashort pulses centered at two-colors (fundamental frequency, $$\omega$$ ω and second harmonic, $$2\omega$$ 2 ω ) can lead to an optimal shape in relativistic intensity driver field that yields such an extraordinarily sensitive control. Conducting a series of two-dimensional (2D) relativistic particle-in-cell (PIC) simulations carried out for currently achievable laser parameters and realistic experimental conditions, we demonstrate that an appropriate combination of $$\omega -2\omega$$ ω - 2 ω along with a precise delay control can lead to more than three times enhancement in the resulting high harmonic flux. Finally, the two-color multi-cycle field synthesized with appropriate delay and polarization can all-optically suppress several attosecond bursts while favourably allowing one burst to occur, leading to the generation of intense isolated attosecond pulses without the need of any sophisticated gating techniques.

Tailoring the waveshape of optical unipolar pulses in a multi-level resonant medium

“…Over recent years significant progress has been achieved in generation of ultra-short pulses up to fewcycle and subcycle duration in the optical range [1][2][3][4][5][6][7][8]. As the result, the possibilities to observe and even control different ultrafast processes in matter has become available [9][10][11][12][13].…”

Recent status of the SYLOS 2 laser system of ELI-ALPS

“…During the second phase, SYLOS 2 the aim was to shorten the pulse duration while maintaining the peak power at the same level 1 . From 2019 this system provided 32 mJ, <7 fs pulses which will be used for electron-acceleration, neutron generation and high-harmonic generation (HHG) in gases and in solid materials [3][4][5] . In total, there are six beamlines calling for high quality pulses and stable laser parameters.…”