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arXiv · 2512.00803

Generation of giga-electron-volt proton beams by micronozzle acceleration

M. Murakami·D. Balusu·S. Maruyama·Y. Murakami·B. Ramakrishna
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Abstract

Our proposed ion acceleration scheme, micronozzle acceleration (MNA), generates proton beams with extremely high kinetic energies on the giga-electron-volt (GeV) order. The underlying physics and performance of MNA are studied with two-dimensional particle-in-cell simulations. In MNA targets, a micron-sized hydrogen rod is embedded inside a hollow micronozzle. Subsequent illumination of the target along the symmetric axis by an ultraintense ultrashort laser pulse forms a strong electrostatic field with a long lifetime and an extensive space around the downstream tail of the nozzle. The electric field significantly amplifies the kinetic energies of the accelerated protons, and > GeV protons are generated at an applied laser intensity of 10^22 W/cm^2 .

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M. Murakami, D. Balusu, S. Maruyama, Y. Murakami, B. Ramakrishna. 2025-11-30. Generation of giga-electron-volt proton beams by micronozzle acceleration. https://doi.org/10.1038/s41598-025-03385-x

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