Achieving Stable Radiation Pressure Acceleration of Heavy Ions via Successive Electron Replenishment from Ionization of a High-Z Material Coating

Among various laser-driven acceleration schemes, radiation pressure acceleration (RPA) is regarded as one of the most promising schemes to obtain high-quality ion beams. Although RPA is very attractive in principle, it is difficult to be achieved experimentally. One of the most important reasons is the dramatic growth of the multi-dimensional Rayleigh-Taylor-like (RT) instabilities. In this talk, we report a novel method to achieve stable RPA [2,3] of ions from laser-irradiated ultrathin foils, where a high-Z material coating in front is used. The coated high-Z material, acting as a moving electron repository, continuously replenishes the accelerating ion foil with comoving electrons in the light-sail acceleration stage due to its successive ionization under laser fields with Gaussian temporal profile. As a result, the detrimental effects such as electron loss induced by the RT and other instabilities are significantly offset and suppressed so that stable acceleration of ions are maintained. [1] B. Qiao et al., PRL 108, 115002 (2012); [2] X. F. Shen, B. Qiao* et al., PRL 118, 204802 (2017); [3] X. F. Shen, B. Qiao* et al., NJP 19, 033034 (2017).