PAC-studies of Sn-doped In2O3: Electronic defect relaxation following the In-111(EC)Cd-111-decay

Perturbed gamma gamma-angular correlation measurements as function of the measuring temperature and the Sn-content have been performed in Sn-doped cubic In2O3 using In-111(EC)(111)d and Cd-111m probes. By comparing the spectra of both isotopes, electronic relaxation phenomena, so-called decay after-effects, following the electron capture radioactive decay of In-111, were established. A time independent loss of the static quadrupole interaction amplitudes was found to be characteristic for the electronic relaxation, and its temperature and doping dependence were measured. The high statistical accuracy of the PAC-data allowed a separation between structural and dynamic effects and the observation of each lattice site's behaviour. Relaxation rates were extracted from numerical simulations based on Blume's theory and related to the predominant electron transport mechanisms in In2O3, especially, with rising Sn-content, to the transition to metallic conduction.