The presence of 3-D magnetic field (strictly speaking, non-axisymmetric magnetic field) brings both challenges and opportunities in fusion plasmas. Specifically, the plasma stability and transport, as well as turbulence, are greatly affected by the 3-D magnetic field. Among various 3-D physics themes, the resonant magnetic perturbation (RMP)-driven, edge-localized-modes (ELM) control has been one of the hottest topics scientifically and technologically.
Considering that ELMs in magnetically confined plasmas would outburst substantial heat and particle fluxes on the divertor and plasma facing components, the full ELM-crash- suppression would help us avoid such harmful damages, so that almost all the major fusion devices have been vigorously searching for a solution. In this regard, as of 2018, the Korea Superconducting Tokamak Advanced Research (KSTAR) located at Daejeon, Korea became the world no. 1 device, in that the longest sustainment of full ELM-crash- suppression over 40 sec has been demonstrated using n=1 RMP (where n refers to the toroidal mode number.
Nonetheless, the detailed physics mechanism to make full ELM-crash- suppression, instead of ELM-crash- mitigation, remains to be clarified, whereas several key physics parameters, such as edge safety factor (q95), collisionality (nu*), and shape effect, have been found. Since the RMP configurations to be installed in ITER (the largest tokamak being built in Southern France, whose size is expected to be comparable to that of future fusion reactor) would be similarly tested in KSTAR, the divertor heat flux profiles and their dependence on 3-D field configurations are being actively investigated.
Currently, such 3-D field physics study plays a role of hub in drawing the attentions of both theoretical and experimental gurus, whose accomplishments would likely be remembered as one of the significant contributions to fusion research forever.
Magnetohydrodynamics/Error Field Study/Turbulent Transport/Neutral Particle Diagnostic Development would belong to the main research interests, as well.