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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Effect of the magnetic impurity on the charge diffusion in highly dilute Ce doped LaMnO3

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Cabrera-Pasca, G. A. [1] ; Bosch-Santos, B. [2] ; Burimova, A. N. [2] ; Correa, E. L. [2] ; Carbonari, A. W. [2]
Total Authors: 5
[1] Univ Fed Para, Fac Ciencias Exatas & Tecnol, BR-68440000 Abaetetuba, PA - Brazil
[2] IPEN CNEN SP, Inst Pesquisas Energet & Nucl, BR-05508000 Sao Paulo - Brazil
Total Affiliations: 2
Document type: Journal article
Source: AIP ADVANCES; v. 10, n. 1 JAN 1 2020.
Web of Science Citations: 0

LaMnO3+delta is a complex oxide, which, depending on the oxygen excess concentration, presents different crystalline structure and interesting magnetic and electric properties such as colossal magnetoresistance, polaron dynamics, multiferroic behavior, and charge-orbital ordering. This complexity requires different characterization techniques to draw a picture as complete as possible allowing a good understanding of these phenomena. Here, we have used the perturbed angular correlation (PAC) technique to measure hyperfine interactions at La and Mn sites of LaMnO3+delta(delta similar to 0.15) using Ce-140 and Cd-111 at La sites as probe nuclei in order to investigate within an atomic scale the magnetic and electric interactions in this compound. The results show that Cd-111 nuclei occupy highly symmetric local sites in agreement with a rhombohedral structure. The magnetic hyperfine field (B-hf) measured with Cd-111 at La sites is very small (B-hf = 0.40 T) due to the supertransferred magnetic field from Mn neighbors through oxygen orbitals. On the other hand, Ce-140 nuclei at La sites present a saturation field of around 3.7 T much higher than that expected for La sites (due to the weak transfer field by superexchange mechanism). In addition, for temperature range above the magnetic ordering (200-300 K) a dynamic hyperfine interaction was observed characterized by the attenuation parameter lambda(T) whose temperature dependence allowed to determine the activation energy (E-a) associated to charge transfer. The polarization of the 4f-electron of Ce impurities affects the local magnetic field at impurity sites as well as the E-a. (AU)

FAPESP's process: 19/15620-0 - Tuning MFe2O4 (M=Co,Ni) nanoparticles for in vivo biomedical applications: Doping with rare earths and biocompatible coating
Grantee:Anastasia Nikolaevna Burimova
Support type: Scholarships in Brazil - Post-Doctorate
FAPESP's process: 14/14001-1 - Project and construction of a digital spectrometer:A more eficient equipment to investigate materials using PAC technique
Grantee:Rajendra Narain Saxena
Support type: Regular Research Grants