The solid state physics programme at ISOLDE: recent developments and perspectives

Abstract

Solid state physics (SSP) research at ISOLDE has been running since the mid-1970s and accounts for about 10%–15% of the overall physics programme. ISOLDE is the world flagship for the on-line production of exotic radioactive isotopes, with high yields, high elemental selectivity and isotopic purity. Consequently, it hosts a panoply of state-of-the-art nuclear techniques which apply nuclear methods to research on life sciences, material science and bio-chemical physics. The ease of detecting radioactivity—<1 ppm concentrations—is one of the features which distinguishes the use of radioisotopes for materials science research. The manner in which nuclear momenta of excited nuclear states interact with their local electronic and magnetic environment, or how charged emitted particles interact with the crystalline lattices allow the determination of the location, its action and the role of the selected impurity element at the nanoscopic state. ISOLDE offers an unrivalled range of available radioactive elements and this is attracting an increasing user community in the field of nuclear SSP research and brings together a community of materials scientists and specialists in nuclear solid state techniques. This article describes the current status of this programme along with recent illustrative results, predicting a bright future for these unique research methods and collaborations.

Incorporation of Cd-Doping in SnO2

“…The measurements could be subjected to the electron conversion process, which is part of the 111m Cd probe decay. This probe can be implanted at ISOLDE-CERN [19] within their solid-state physics program [24]. Moreover, it is possible to perform simultaneous 111 In and 111m Cd implantations [25].…”

A generalized fitting tool for analysis of two-dimensional channeling patterns

“…1). Various key aspects of the technique have been described in detail previously: ISOLDE/CERN as the radioactive beam facility [45][46], the implantation and measurement chamber [47], the position sensitive electron detectors [36,[40][41], and the "manybeam" simulation software for electron channeling [33,36]. The fitting software makes the connection between the data from the detector and the results of many-beam simulations: the angular anisotropy is measured as a 2D histogram of counts, where each bin represents the counts in a pixel which covers an area of specific angular range with respect to the crystal axis; for quantitative analysis, the 2D histograms, also called patterns, are then compared to simulated data using a fitting routine.…”

57Fe Mössbauer study of epitaxial TiN thin film grown on MgO (1 0 0) by magnetron sputtering

“…Mössbauer spectroscopy is particularly useful in this regard, due to its sensitivity to the immediate atomic environment of the probe nucleus through electric interaction and magnetic hyperfine interaction (up to second next nearest neighbours) [18]. Using implantation of radioactive parent isotopes (emission Mössbauer spectroscopy, eMS) in the sample of interest, one can study extremely dilute levels (<10 -3 at%) [19]. With eMS, the dilute Fe atoms in ZnO/AlN/GaN were confirmed in a paramagnetic state, ruling out the assumption of ordered magnetic origin of the dilute magnetic properties in ZnO/AlN/GaN [20] [21] [22].…”

“…In this work, we employ 57 Fe eMS by implantation of short-lived radioactive 57 Mn + ions in TiN at an extremely dilute level using the ISOLDE facility at CERN [25] [19]. This is especially powerful for atomic scale investigation of local structure defects and the possible diluted magnetic properties of TiN nanostructures.…”