Development of high intensity ion source for plasma–wall interaction research

Understanding plasma–wall interactions (PWI), including erosion, redeposition, and hydrogen retention in plasma-facing materials, is a key scientific issue for ensuring the stable and safe operation of fusion reactors. To investigate the dynamic effects on a surface under such a low-energy ion flux in fusion plasma boundary, a novel axial double-hollow-cathode high-intensity ion source (Axial-DHIS) was developed in this work. The discharge characteristics and ion spectra of the extracted ion beam were systematically analyzed, and the stable operating regime of the source was identified. Under optimized conditions, a stable deuterium ion beam with a total extracted current of up to 2.4 mA was achieved through a 1.0 mm extraction aperture. The beam was dominated by D + 2 ions, which accounted for up to 75% of the total composition. Furthermore, when operating with argon, the Axial-DHIS can also produce multiply charged argon ions with charge states up to +6. With its compact structure, high discharge efficiency, and excellent ability to deliver high-current-density and multiply charged ion beams, the Axial-DHIS ion source provides an effective tool for PWI studies and offers valuable support for fusion-related research, medium- and low-energy ion irradiation experiments, and material modification.