Polarization-dependent fast-electron emission in high-temporal-contrast femtosecond laser plasmas

Abstract

Generation and transport fast electrons play an important role in intense laser interaction with dense plasma. Here, fast electron generation from a planar aluminum target obliquely irradiated at large incident angle by an ultrashort high-temporal-contrast relativistic laser pulse is experimentally studied. Simulations show that for near-relativistic laser intensity, s-polarized lasers above a certain energy threshold can generate energetic electrons (Ee>500keV) with high yield, which is different from the case of low laser contrast. It is also shown that the most energetic electrons are emitted along the target surface and accelerated to high energies. The key features of the acceleration regimes of lasers with different polarizations are also given.