We demonstrate a scheme for enhanced fast electron transport in fast ignition by using a tapered cone. By simulating the interaction of relativistic ps laser pulse with a gold cone via two-dimensional partical-in-cell (PIC) simulation, we find that the tapered cone suppresses longitudinal sheath field generation compared to the traditionally used flat-topped cone, while enhancing transverse sheath fields. This configuration exhibits advantages in guiding low-energy fast electrons and suppression of their lateral divergence during transmission into high-density targets. As the cone insertion depth into the target increases, the advantage of tapered cone is weakened. We further explore the effects of material and plasma density and laser intensity and find that the benefits of the tapered cone maintain under different parameters, though the critical insertion depth shifts accordingly.
 

fast ignition,inertial confinement fusion,particle-in-cell simulation