The differences and similarities between the internal transport barriers (ITBs) of tokamak and
helical plasmas are reviewed. By comparing the characteristics of the ITBs in tokamak and …

Neoclassical transport processes are important to the understanding of plasma confinement
physics in doubly periodic magnetized toroidal plasmas, especially, after the impact of the …

The physics model of electron cyclotron heating (ECH) and current drive (ECCD) is
becoming well validated through systematic comparisons of theory and experiment. This …

The key result of the present work is the theoretical prediction and observation of the
formation of a new type of transport barrier in fusion plasmas, called F-ATB (fast ion-induced …

Extremely hollow profiles of impurities (denoted as “impurity hole”) are observed in the
plasma with a steep gradient of the ion temperature after the formation of an internal …

The improvement of core electron heat confinement has been realized in a wide range of
helical devices such as CHS, LHD, TJ-II and W7-AS. Strongly peaked electron temperature …

Stellarators have much in common with tokamaks, and some attractive features relative to
them—disruption-free performance, and no requirement for current drive to produce a …

The deuterium (D) operation was initiated in the LHD in 2017. In the first campaign of the D
experiments, we successfully extended the high temperature regime in the LHD. The new …

The large helical device (LHD) is one of the world's largest superconducting helical system
fusion-experiment devices. Since the start of experiments in 1998, LHD has extended its …

The central electron temperature has successfully reached up to 7.5 keV in large helical
device (LHD) plasmas with a central high-ion temperature of 5 keV and a central electron …