High-flux neutron generation by laser-accelerated ions from single- and double-layer targets

Area of Science:

• Nuclear physics and plasma physics
• Laser-driven particle acceleration
• Applications in materials science and astrophysics

Background:

• Ultraintense, short-pulse lasers offer compact sources for high-flux neutron beams.
• Neutrons are crucial for applications like nondestructive probing, fusion materials research, and laboratory astrophysics.
• Existing neutron sources face limitations in flux and compactness.

Purpose of the Study:

• To optimize neutron production from ion-induced nuclear reactions using 1-PW, 20-fs laser systems.
• To investigate strategies for enhancing ion acceleration for improved neutron yield.
• To compare the performance of single-layer and double-layer targets for neutron generation.

Main Methods:

• Coupling particle-in-cell and Monte Carlo numerical simulations.
• Utilizing ultrathin solid foils as laser-irradiated targets, with and without a preceding plasma layer.
• Analyzing the energy and angular spectra of laser-accelerated ions.
• Simulating neutron generation via nuclear reactions in beryllium and lead converters.

Main Results:

• Identified configurations yielding neutron fluxes up to [Formula: see text] in [Formula: see text]-cm-thick converters.
• Achieved instantaneous neutron fluxes exceeding [Formula: see text] at the backside of [Formula: see text]-[Formula: see text]m-thick converters.
• Predicted time-averaged neutron yields significantly above experimental records, even with thin foil targets.
• Foreseen a substantial increase in time-averaged yield using double-layer targets.

Conclusions:

• Optimized ultrathin target configurations with ultraintense lasers can achieve record-breaking neutron yields.
• Double-layer targets offer enhanced performance for maximizing neutron production.
• These laser-driven neutron sources show great promise for various scientific and technological applications.