Absorption of variable contrast femtosecond laser pulses by overdense plasmas in the relativistic regime

摘要

The efficiency of the laser energy transfer to the matter plays a central role in different physical processes and phenomena specific to laser produced plasmas. It has been shown that the energy absorption has an impact on various physical processes, including energetic particle acceleration, high harmonics generation and hard X-ray production. Absorption depends on large number of physical conditions which can control and optimize the coupling of the laser energy [1]. In particular, recent studies concentrated on the dependence of laser polarization and pre-plasma density profiles on these processes at ultrahigh laser intensities [2,3].