INSTITUTO DE FISICA LA PLATA
Unidad Ejecutora - UE
congresos y reuniones científicas
Dynamic hyperfine interactions in 111In-doped Y2O3 semiconductor: a first principles scenario
E. L. MUÑOZ; A. W. CARBONARI; M. RENTERÍA
Conferencia; 4th Joint Meeting of the 16th International Conference on Hyperfine Interactions & 20th International Symposium on Nuclear Quadrupole Interaction; 2012
A combined theoretical and experimental approach applied to the determination of physical quantities such as the electric-field-gradient (EFG) tensor at impurity sites in doped semiconductor oxides is a powerful tool for the characterization of structural, electronic and magnetic properties induced by the impurities in these systems. In this work, we present results of gamma-gamma Perturbed-Angular-Correlations (PAC) experiments performed on 111In((EC)→111Cd)-diffused Y2O3 polycrystalline pellets, designed to study in detail the temperature dependence of dynamic hyperfine interactions already observed at 111Cd probes in some bixbyite oxides [1-3]. The PAC measurements were performed in the temperature range 10-900 K. The PAC results were analyzed enlighten by electronic structure first-principles calculations performed with the Full-Potential Augmented-Plane Wave plus local orbital (FP-APW+lo) method in the framework of the Density Functional Theory (DFT). From this double approach, we could determine the temperature dependence of the EFG tensor at 111Cd probes located at both C and D cation sites of the Y2O3 bixbyite structure and to propose a scenario that explains the origin of the dynamic interactions occurred after of the electron-capture decay of the 111In nuclei. This scenario is based on the EFG dependence on the life-time of electron holes trapped at the impurity acceptor level introduced by the Cd atom at the top of the valence band of the Y2O3 semiconductor.References A.G. Bibiloni, C.P. Massolo, J. Desimoni, L.A. Mendoza-Zelis, F. H. Sanchez, A.F. Pasquevich, L. Damonte and A.R. Lopez-García, Phys. Rev. B 32 2393 (1985). S. Habenicht, D. Lupascu, M. Uhrmacher, L. Ziegeler. K.P. Lieb y ISOLDE collaboration, Z. Phys. B 101, 187 (1996). A. Bartos, K.P. Lieb, A.F. Pasquevich, M. Uhrmacher e ISOLDE collaboration, Phys. Lett. A 157, 513 (1991).