Stabilization of primary mobile radiation defects in MgF2 crystals

V. M. Lisitsyn, L. A. Lisitsyna, A. I. Popov, E. A. Kotomin, F. U. Abuova, A. Akilbekov, J. Maier

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

Non-radiative decay of the electronic excitations (excitons) into point defects (F-H pairs of Frenkel defects) is main radiation damage mechanism in many ionic (halide) solids. Typical time scale of the relaxation of the electronic excitation into a primary, short-lived defect pair is about 1-50 ps with the quantum yield up to 0.2-0.8. However, only a small fraction of these primary defects are spatially separated and survive after transformation into stable, long-lived defects. The survival probability (or stable defect accumulation efficiency) can differ by orders of magnitude, dependent on the material type; e.g. ∼10% in alkali halides with f.c.c. or b.c.c. structure, 0.1% in rutile MgF2 and <0.001% in fluorides MeF2 (Me: Ca, Sr, Ba). The key factor determining accumulation of stable radiation defects is stabilization of primary defects, first of all, highly mobile hole H centers, through their transformation into more complex immobile defects. In this talk, we present the results of theoretical calculations of the migration energies of the F and H centers in poorely studied MgF2 crystals with a focus on the H center stabilization in the form of the interstitial F2 molecules which is supported by presented experimental data.

Original languageEnglish
Pages (from-to)24-28
Number of pages5
JournalNuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
Volume374
DOIs
Publication statusPublished - 1 May 2016

Keywords

  • Excitons
  • First principles calculations
  • H and F centers
  • Radiation defects
  • Rutile MgF

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Instrumentation

Fingerprint Dive into the research topics of 'Stabilization of primary mobile radiation defects in MgF<sub>2</sub> crystals'. Together they form a unique fingerprint.

  • Cite this