Towards pump-probe experiments of defect dynamics with short ion beam pulses

TL;DR

This paper discusses the development of the NDCX-II accelerator, capable of delivering short, intense ion pulses for pump-probe experiments to study defect dynamics in materials.

Contribution

It introduces a novel induction linear accelerator designed for short ion pulse delivery, enabling new pump-probe studies of defect dynamics.

Findings

Successful beam pulse shaping experiments

Predicted volumetric heating of targets to ~30,000 K

Feasibility of pump-probe defect studies with short ion pulses

Abstract

A novel, induction type linear accelerator, the Neutralized Drift Compression eXperiment (NDCX-II), is currently being commissioned at Berkeley Lab. This accelerator is designed to deliver intense (up to 3x1011 ions/pulse), 0.6 to ~600 ns duration pulses of 0.13 to 1.2 MeV lithium ions at a rate of about 2 pulses per minute onto 1 to 10 mm scale target areas. When focused to mm-diameter spots, the beam is predicted to volumetrically heat micrometer thick foils to temperatures of ~30,000 K. At lower beam power densities, the short excitation pulse with tunable intensity and time profile enables pump-probe type studies of defect dynamics in a broad range of materials. We briefly describe the accelerator concept and design, present results from beam pulse shaping experiments and discuss examples of pump-probe type studies of defect dynamics following irradiation of materials with intense, short ion beam pulses from NDCX-II.