Laser beam filamentation and filamentation instability in ultrarelativistic laser-plasma interaction: influence of relativistic effect and plasma nonuniformity

In this work, influence of intense relativistic influence and plasma nonuniformity on ultrarelativistic laser beam filamentation and filamentation instability has been investigated in homogeneous and inhomogeneous plasma. The results are shown that, in ultrarelativistic laser-plasma interaction, relativistic effect plays a crucial role on beam filamentation and self-focusing, and plasma inhomogeneity further increases beam filamentation, while it also strengthens filamentation instability. To avoid filamentation instability, the research results show that it should try to reduce plasma inhomogeneity in laser-plasma interaction.