Fundamental Phenomena and Applications of Swift Heavy Ion Irradiations

Abstract

This review concentrates on the specific properties and characteristics of damage structures generated with high-energy ions in the electronic energy loss regime. Irradiation experiments with so-called swift heavy ions (SHI) find applications in many different fields, with examples presented in ion-track nanotechnology, radiation hardness analysis of functional materials, and laboratory tests of cosmic radiation. The basics of the SHI-solid interaction are described with special attention to processes in the electronic subsystem. The broad spectrum of damage phenomena is exemplified for various materials and material classes, along with a description of typical characterization techniques. The review also presents state-of-the-art modeling efforts that try to account for the complexity of the coupled processes of the electronic and atomic subsystems. Finally, the relevance of SHI phenomena for effects induced by fission fragments in nuclear fuels and how this knowledge can be applied to better estimate damage risks in nuclear materials is discussed.

Comprehensive Understanding of Hillocks and Ion Tracks in Ceramics Irradiated with Swift Heavy Ions

“…Another possible factor is the strength of ionic bonding, i.e., materials with a higher degree of ionicity recrystallize easily [19,56]. Non-amorphizable ceramics include many ionic crystals.…”

Observation of latent ion tracks in semicrystalline polymers by scanning electron microscopy

“…Thus, our data for the ions with different atomic numbers show a tendency which is typical of the track radius versus energy loss dependence, that is, with a sharp increase at lower dE/dx and a moderate slope at higher dE/ dx. 3,18 The apparent radius of the Xe, Au, and Bi tracks in the SEM images is approximately 15-20 nm. This value correlates well with the radius of the track halo found in the etching experiments with single tracks of ions with high atomic numbers in similar PET foils.…”

“…1,2 Swift heavy ions (SHI)-a form of particle radiation-have sufficient energy and mass to penetrate solids in a straight line and produce a continuous damage trail, called a latent track. 2,3 Over the last 60 years, the ability of SHI to produce latent tracks has become the reason for extensive fundamental and applied research works. 3 Both the mechanisms of track formation and the numerous applications in fields such as material science, nanotechnology, biophysics, and cosmic ray simulations have attracted the attention of the scientific community.…”

“…Sometimes the track structure is more complex and consists of an amorphous core surrounded by a disordered crystalline shell. 3 Methodologically, TEM requires great effort in sample preparation and the success largely depends on the sample quality. Small angle scattering of X-rays and neutrons (SAXS and SANS, respectively) provides valuable data on the size and density deficit in latent tracks in different matrices, including polymers.…”

“…Small angle scattering of X-rays and neutrons (SAXS and SANS, respectively) provides valuable data on the size and density deficit in latent tracks in different matrices, including polymers. 3,[10][11][12][13] Sophisticated TEM investigations yielded estimates of 6-10 nm for the diameter of a central track region of ion tracks in polyethylene (PE), polyethylene terephthalate (PET), and polyimide (PI). [14][15][16][17] Both TEM and small angle scattering characterize the ion track in polymers as a zone with a lower gravimetric density, that is, the zone that is called the "track core."…”