Modulation of absorption manner in helicon discharges by changing profile of low axial magnetic field Project supported by the National Natural Science Foundation of China (Grant Nos. 11175024, 11375031, and 11505013), the Beijing Natural Science Foundation of China (Grant No. KZ201510015014), and the Beijing Municipal Natural Science Foundation, China (Grant No. 4162024). |
(color online) Axial profiles of (a) electron density and (b) electron temperature along the discharge tube in Case 2 at different Bex values and a 140-W RF power. |