Application of encapsulated hollow gold nanocluster targets for high-quality and quasi-monoenergetic ions generation

Abstract

Abstract With persistent progress in ultra-intense laser pulses, Coulomb explosions (CE) of spherical nanoclusters can in principle produce high-quality quasi-monoenergetic ions. Focusing on using CE framework, in this paper, I have proposed a target scheme to accelerate the light/heavy ion beams. The scheme relies on encapsulating a hollow gold nanocluster inside a hollow proton-carbon (HC) nanosphere. The ability of this suggestion has been simulated by the two-dimensional particle-in-cell code (EPOCH). Simulation results exhibit that a hollow gold cluster can positively increase the electron extraction. This condition may improve the acceleration of low-divergence H+, C6+, and Au67+ ions. The simulation shows that at the end of the interaction, for a gold cluster with an optimal hollow radius of 91.3 nm, the cut-off energy of H+, C6+, and Au67+ are about 54.9, 51.5, and 54.9 MeV u−1, respectively. In this case, an increase of about 52% for H+ and 61% for C6+ is obtained, contrast to bare HC hollow nanosphere (i.e. a hollow nanosphere with no cluster), while the relative divergence decreases to 1.38 and 1.86, respectively, for H+ and C6+ ions. I have also compared my simulation results with another proposed target structure composed of a void area with an optimum diameter of 70.4 nm between the fully-gold nanocluster and HC nanosphere. I have exhibited that the results are improved, contrast to bare nanosphere. However, the cut-off energy suppression and angular divergence increase are shown compared with encapsulated hollow gold nanocluster structure.