Pulsed neutron source from interaction of relativistic laser pulse with micro-structure assisted pitcher–catcher target

Abstract

Abstract Neutron detection technology is a powerful method for characterizing fundamental and industrial materials, such as magnetic materials, nanomaterials, polymers, and biological substances. A compact pulsed neutron source is desired, as the traditional way of producing high-yield neutrons depends mainly on large-scale accelerators or fission reactors. Here, we propose a scheme to generate a high-yield pulsed neutron source by using a > 100 fs relativistic laser pulse interacting with a micro-structure assisted pitcher–catcher target. Three-dimensional particle-in-cell and Monte Carlo hybrid simulations demonstrate that an energetic deuterium ion beam with a cutoff energy of 75 MeV and a 7.23 % laser-to-deuterium energy conversion efficiency can be obtained with a laser pulse of intensity 1.37 × 10 20 W cm−2, duration 330 fs, power 34 TW and energy 6.7 J. When they strike the following lithium fluoride converter of thickness 2 cm, a large number of neutrons are thus produced via a 7Li(d,n) nuclear reaction. The neutron yield is up to 109 and its pulse duration is as short as 20 ps. This scheme could be realized in laboratories with current hundreds-of-terawatt or multi-petawatt laser facilities.