Role of low temperature resistivity on fast electron transport in disordered aluminium and copper

Abstract

To determine the link between the onset of the filamentation instability and the low temperature resistivity of the cold-electron plasma a comparison between the transport of fast electrons through disordered aluminium and copper targets is made using the hybrid code Zephyros. The filamentation instability is suppressed at laser intensities below 5×10 19 W cm −2 for materials where the resistivity of the material is lower than 1µΩm at 1eV. Interestingly copper targets show larger resistive magnetic field growth, and as a result more collimation of the electron beam, despite having a consistently smaller resistivity at lower temperatures than that of aluminium. The increase in magnetic field strength is responsible for the suppression of the filamentation instability. This is due to the resistive filamentation growth rate for copper and aluminium, under identical conditions, being numerically very close.