Enhanced hot electron generation via laser interference

Abstract

The interaction of two interfered picosecond laser pulses with overdense plasma and the resulting hot electron generation are studied by particle-in-cell simulation. We find that the yield and temperature of forward hot electrons can be significantly increased when laser interference fringes have a period around [Formula: see text] and the angle between the two pulses is about [Formula: see text]. The enhancements result from local intensity increase at laser interference fringes and the plasma surface structure formed by laser pulses. The optimal angle and fringe period are analyzed, and the dependence between the optimal period and plasma density scale length is discussed. This work could be applied in hot electron generation and the resulting ion acceleration, fast ignition of laser fusion, etc.