Microtube implosion1-3 is a novel scheme to generate ultrahigh magnetic fields of the megatesla order. The microtube implosion is driven by ultraintense and ultrashort laser pulses. In the original concept of the microtube, however, uniform magnetic fields of the kilotesla order must be pre-seeded along the microtube axis to induce Larmor gyromotion of the imploding ions and electrons. Recently we have found that a structured microtube target can also generate ultrahigh magnetic fields even without seeded magnetic fields. In this case, due to the microbrade structure made on the inner surface of the microtube, vortex flows of relativistic electrons are collectively formed around the center of the cylindrical target to induce ultrahigh spin current.

We apply the microtube implosion to fusion reactions such as p11B as well as orthodox DT (deuterium-tritium) and/or DD (deuterium-deuterium) reactions. We address the optimization of the laser and target parameters for those fusion reactions. The detail of the analysis in terms of two- and three-dimensional particle simulations are provided to clarify the underlying physics.

[1] M. Murakami et al., Sci. Rep. 10, 16653 (2020).
[2] D. Shokov et al., High Power Laser Sci. Eng. 9, e56 (2021).
[3] Y. Gu and M. Murakami, Sci. Rep. 11, 23592 (2021).