Positron lifetime and Doppler broadening studies were made of vacancy-type defects in polycrystalline GeTe and (GeTe)1-x(AgBiTe2)x, where x was equal to 0, 0.03, 0.05, 0.1, 0.15, 0.2 or 1. The values of the lifetimes which were observed were explained as being due to positron and positronium saturated trapping at vacancies and vacancy clusters. The interdependence of the mean positron lifetime and hole concentration was considered.

Study of Defects in GeTe and GeTe-AgBiTe2 Solid Solutions by Positrons. M.Misheva, I.Avramova, S.Plachkova, N.Djourelov: Acta Physica Polonica A, 2001, 99[3-4], 423-8