Overview of photo-neutralization techniques for negative ion-based neutral beam injectors in future fusion reactors

High power multiple mirrors optical path design and simulation of photo-neutralization

“…The energy loss of the neutral beam system mainly comes from low neutralization efficiency, and the two key links are the selection of ion source and neutralizer. Due to the upper limit of the neutralizing efficiency of positive ion sources, as well as the limitations of solid targets, gas targets, metal vapor targets, and plasma targets, Photo-neutralization of neutralizing beams technology has high neutralizing efficiency (>80%) and wall-plug efficiency (>60%) in principle, and has minimal impact on the load of beam components, making it one of the most promising technologies for future nuclear fusion NBI [1,2] . In simple termst, the negative ions are accelerated by an accelerator and filtered by Electrical Residual Ion Dump(ERID) to form a high-energy negative ion beam, which is injected into a neutralizer and collides with an independently generated high-energy laser beam.…”