Speaker
Vitor Bras De Sequeira Amaral
(University of Aveiro)
Description
Complex oxides, particularly manganites (R-D)MnO3 present a wealth of behaviours associated with coupled spin, lattice, charge and orbital degrees of freedom, that can be controlled by chemical doping. Perturbed Angular Correlation (PAC) studies in several systems were performed to locally probe these effects using the electric field gradient (EFG) and magnetic hyperfine field generated by the charge and spin distribution around the probe. A comprehensive account, based on the real-space atomic-scale information obtained, first-principle calculations and complementary macroscopic properties studies is given on phenomena like:
-lattice and polaron dynamics, phase separation, intrinsic local inhomogeneities [1]
-charge-ordering and electric polarization [2]
-the role of structural distortions and symmetry changes on magnetic and multiferroic materials
Some prospects for new challenging phenomena and systems to be studied using radioactive isotopes are also anticipated.
[1] A.M.L. Lopes, J.P. Araújo, J.J. Ramasco, V.S. Amaral, R. Suryanarayanan, J.G. Correia
Physical Review B-Rapid Communications, 73, 100408(R) (2006)
[2] A.M.L. Lopes, J.P. Araujo, V.S. Amaral, J.G. Correia, Y.Tomioka and Y. Tokura
Physical Review Letters,100, 155702 (2008)
Author
Vitor Bras De Sequeira Amaral
(University of Aveiro)
Co-authors
Armandina Lopes
(CFNUL, Univ. Lisboa, 1649-003 Lisboa, Portugal)
João Amaral
(Dep. Física and CICECO, Univ. Aveiro, 3810-193 Aveiro, Portugal)
João Guilherme Correia
(CERN EP, CH 1211 Geneve 23, Switzerland and 6ITN, E.N. 10, P-2685 Sacavém, Portugal)
João Nuno Gonçalves
(Dep. Física and CICECO, Univ. Aveiro, 3810-193 Aveiro, Portugal)
João Pedro Araújo
(Dep. Física and IFIMUP, Univ. Porto, 4169-007 Porto, Portuga)
Pedro Tavares
(CQ-VR, UTAD, 5001-801 Vila Real, Portugal)
Tânia Mendonça
(Dep. Física and IFIMUP, Univ. Porto, 4169-007 Porto, Portugal and CERN EP, CH 1211 Geneve 23, Switzerland)
