Speaker
Tania Manuela De Melo Mendonca
(IFIMUP, Phys. Dept., FCP, Rua do Campo Alegre 687, P-4150 Porto, Portugal)
Description
The perovskite manganites of the family RMnO3 (R=Eu, Gd, Ho, Y, Er and Lu) show different competing orders, e.g. orbital, magnetic, and dielectric, that lead to intriguing properties as colossal magnetoresistance and multiferroic behaviour.
Looking forward to investigate locally the interplay between structural, electric and magnetic degrees of freedom, samples have been synthesized via sol-gel methods and studied with the Perturbed Angular Correlation (PAC) technique.
In this first work we have limited the use of PAC to measure the Electric Field Gradient (EFG) / Magnetic Hyperfine Field (MHF) in a series of samples with different rare-earths (R), aiming to find a correlation between these local parameters and the ionic radius of the R element.
At ISOLDE small pellets were implanted with 111mCd and subsequently annealed to remove implantation defects. The PAC measurements have been performed from 10K up to 473K for the same samples. These results are compared with the ones previously obtained for other perovskite manganites like LaMnO3, PrMnO3 and CaMnO3. Complementary information is obtained through X-ray diffraction data and SQUID measurements on the same samples. The unit-cell parameters, the bond distances and angles are also factors that can be related to the effects under study, and their revision is also proposed in order to complete the microscopic characterization of these compounds.
Author
Tania Manuela De Melo Mendonca
(IFIMUP, Phys. Dept., FCP, Rua do Campo Alegre 687, P-4150 Porto, Portugal)
Co-authors
Andre Pereira
(IFIMUP, Phys. Dept., FCP, Rua do Campo Alegre 687, P-4150 Porto, Portugal)
Armandina Lima Lopes
(Phys. Dept. & CICECO, Universidade de Aveiro, 3810-193 Aveiro, Portugal)
Joao Guilherme Correia
(Instituto Tecnológico e Nuclear, E. N. 10, P-2686-953 Sacavém, Portugal)
Joao Pedro Araujo
(IFIMUP, Phys. Dept., FCP, Rua do Campo Alegre 687, P-4150 Porto, Portugal)
Joao Sequeira Amaral
(Phys. Dept. & CICECO, Universidade de Aveiro, 3810-193 Aveiro, Portugal)
Pedro Bandeira Tavares
(Chemistry Dept. and CQ-VR, Universidade de Trás-os-Montes e Alto Douro, P-5000-911 Vila Real, Portugal)
Vitor Sequeira Amaral
(Phys. Dept. & CICECO, Universidade de Aveiro, 3810-193 Aveiro, Portugal)
