Ab initio study of Cd-doped Sc2O3 semiconductor and comparison with 111Cd PAC experiments

E. MUÑOZ, D. RICHARD, L. A. ERRICO, Y M. RENTERÍA.

Buenos Aires

Workshop; Workshop "At the Frontiers of Condensed Matter physics IV"; 2008

Comite internacional

Trabajo presentado en forma de poster durante la reunionThe combination of hyperne techniques andtheoretical simulations based on ab initio calculationshas been shown to be a powerful tool to unravelstructural characterizations in the atomic scale ofimpurities in solids. A recent example has been thestudy of SnO:Cd, where ab initio calculations [1] andPerturbed Angular Correlations (PAC) measurementswere combined to describe the dynamic hyperneinteractions observed at 111Cd impurities in the SnOsemiconductor [2], originated in the electron-capture(EC) decay after-eects (AE) of the parent isotope111In. In this work, we present an ab initio studyon the Cd-doped Sc2O3 semiconductor that enablesa description of the dynamic interactions observedin PAC experiments using 111In-implanted Sc2O3samples. The theoretical study was performed at Cdimpurities located at both cationic sites C and D ofthe Sc2O3 Bixbyite structure, using the AugmentedPlane Waves + Local Orbital (APW+LO) methodin the framework of the Density Functional Theory(DFT), with an impurity dilution of 1:48. Westudied the EFGs for dierent charge states of theCd impurity (neutral supercell and 1-electron addedsupercell). These theoretical results are comparedwith PAC results reported by Bartos et al. [3], inwhich an strong damping of the spin-rotation spectrawas observed at low temperatures (lower than 600K).This damping is produced by dynamic hyperneinteractions that were correlated with the EC decayAE of 111In probes. Our ab initio results are inexcellent agreement with the experimental EFGs andcan explain the origin of the dynamic interactionsobserved.