6533b861fe1ef96bd12c4314

RESEARCH PRODUCT

Thermal annealing of radiation defects in MgF2 single crystals induced by neutrons at low temperatures

A.m. MoskinaE. ElstsEugene A. KotominAnatoli I. PopovAnatoli I. PopovI. MakarenkoS. PazylbekV.k. KuzovkovZh. T. KaripbayevZh. T. Karipbayev

subject

Nuclear and High Energy PhysicsMaterials scienceAnnealing (metallurgy)Ionic bonding02 engineering and technologyElectronRadiationAtmospheric temperature range021001 nanoscience & nanotechnology01 natural sciencesMolecular physicsIon0103 physical sciencesIrradiation010306 general physics0210 nano-technologyInstrumentationRecombination

description

Abstract Primary radiation defects in ionic solids consist of Frenkel defects – pairs of defects - anion vacancies with trapped electrons (F-type centers) and interstitial ions. Upon temperature increase after irradiation, the electronic F-type centers are annealed due to recombination with mobile interstitials. Analysis of the recombination (annealing) kinetics allows us to obtain important information on the interstitial migration. At high radiation doses more complex dimer (F2-type) centers are observed in several charge states, which are well distinguished spectroscopically. We analysed here available experimental kinetics of the F2-type center annealing in MgF2 in a wide temperature range (300–1000 K). The results of the electron, neutron and ion irradiation are compared. The phenomenological theory of the recombination kinetics of radiation defects takes into account the interstitial ion diffusion and recombination with the F2-centers as well as mutual sequential transformation with temperature growth of three types of experimentally observed dimer centers: F2 (1); F2 (2), F2 (3) (which differ tentatively by effective charges with respect to the host crystalline sites: 0, +1, +2).

https://doi.org/10.1016/j.nimb.2020.07.026