In the realm of laser-driven proton acceleration, a team of researchers from the Institute of Applied Physics and Computational Mathematics in Beijing, China, has made a significant stride. Led by Guanqi Qiu, the team has proposed a novel acceleration scheme that could potentially reduce the dependence on large-scale laser facilities for medical and scientific applications.
The researchers have demonstrated that by reducing the focal spot size of the laser, proton energy can be enhanced substantially even at lower laser energies. Through particle-in-cell simulations and theoretical modeling, they found that at a spot size of 0.8 micrometers, the proton energy was increased by 83.5% compared to conventional spot sizes of 3 micrometers. This enhancement is attributed to the increased ponderomotive force at smaller spot sizes, which drives electrons and generates stronger charge-separation fields that propagate faster.
To further optimize proton energy, the team analytically derived an optimal electron density profile. This profile enables phase-stable proton acceleration, resulting in an additional 60% increase in proton energy. The researchers emphasize that these results are robust across various parameter variations, suggesting that advanced focusing techniques and optimal plasma profiles could indeed reduce the requirement for high laser energy.
The practical implications for the energy sector are significant. Laser-driven proton acceleration has potential applications in cancer therapy, where high-energy protons are used to target tumors. By enhancing proton energy at lower laser energies, this research could lead to more compact and cost-effective laser facilities for medical use. Furthermore, the findings could contribute to advancements in nuclear fusion research, where laser-driven proton acceleration is a key technique.
The research was published in the journal Physical Review Letters, a prestigious publication in the field of physics. The study opens up new avenues for exploring efficient and cost-effective laser-driven proton acceleration, potentially revolutionizing medical and scientific applications that rely on high-energy protons.
This article is based on research available at arXiv.