Dynamics of relativistic electrons propagating in a funnel-guided target.

Hot electron transport in a funnel-guided target is investigated using two-dimensional hybrid simulations. Relativistic electrons generated by a petawatt picosecond short-pulse laser interacting with a gold slab are guided by a funnel to the compressed core region of the fuel. It is shown that as the energetic electrons propagate into the compressed core, the interface magnetic fields in the inner and outer surfaces of the funnel can change sign so that the fast electrons are efficiently guided in the gold funnel to reach the dense core. It is also shown that with funnel guiding, fuel heating is enhanced compared to that without the funnel. The findings here may be useful in the design of more efficient fast-ignition schemes, as well as in other applications involving transport and heating of energetic electrons in targets. [ABSTRACT FROM AUTHOR]