Todas as publicações do grupo de pesquisa podem ser encontradas no Currículo Lattes do coordenador conforme link. Abaixo são elencadas apenas algumas publicações representativas ao longo dos anos e ao lado é possível fazer download de algumas selecionadas.

 

(18) New route for hollow material

M. Rivaldo-Gómez, F. F. Ferreira, G. T. Landi & J.A. Souza

Scientific Reports 6, 32107 (2016); http://www.nature.com/articles/srep32107

crystal_struture

 

 

(17) Influence of chemical doping and hydrostatic pressure on the magnetic properties of Mn1−xFexAs magnetocaloric compounds

L. Rocco, A. de Campos, A. Magnus G. Carvalho, A. O. Santos, L. M. da Silva, S. Gama, P. von Ranke, N. A. de Oliveira, A. A. Coelho, L. P. Cardoso, and J. A. Souza

Phys. Rev. B 93, 054431 (2016)

 

(16) Hierarchically structured nanowires on and nanosticks in ZnO microtube

M. Rivaldo-Gómez, G. A. C. Pasca, A. Zúñiga, A. W. Carbonari, and J. A. Souza.

Scientific Reports 5, 15128 (2015); http://www.nature.com/articles/srep15128

 

(15) Microtubes decorated with nanowires

Applied Physics Letters 106, 213104 (2015); doi: 10.1063/1.4921795

M. Rivaldo-Gómez, A. Zuniga, D. Criado, J. Schoenmaker, and J. A. Souza

 

(14) Magnetic and electrical properties assisted by local distortions in multiferroic compounds

local_distotion2

PeNSeM group publishes a comprehensive study on the magnetic and electrical properties through macroscopic and local characterizations on multiferroics. An analysis of the temperature evolution of local distortions, which was obtained by perturbed angular correlation measurements, revealed an anomalous behavior of the quadrupolar frequency and asymmetry parameter below the antiferromagnetic ordering temperature for Bi2Mn4O10 and Bi2Fe4O9 compounds. The combined results suggest correlations between magnetic, electric, and elastic interactions. At high temperature, we have observed that the hopping frequency and activation energy in the electrical transport mechanism are close related to hyperfine parameters, electrical field gradient and asymmetry parameter, due to modifications in the equilibrium positions of oxygen atoms conforming octahedral, pyramidal, and tetrahedral environments. Anharmonic lattice effects are much more pronounced in a temperature range close to room temperature.

The article was published in the Journal of alloys and compounds volume 651 Pages 405–413. see the article at doi:10.1016/j.jallcom.2015.08.165 or a copy of the manuscript here.

 

(13)  Possible misleading interpretations on magnetic and transport properties in BiFeO3nanoparticles caused by impurity phase.

Physics Letters A 379, 1549-1553 (2015); doi: j.physleta.2015.03.035

Fabian E.N. Ramirez, Gabriel A.C. Pasca, Jose Antonio Souza

Misleading

We have performed a systematic study on the magnetization and electrical polarization of BiFeO3nanoparticles. Two sets of BiFeO3nanoparticlesamples were synthesized by employing a wet chemical method with slightly different route. Our results suggest that the presence of very small amount of magnetic impurity phase, not detected by XRD, can strongly influence the magnetic and electrical properties of this system. The presence of impu-rity affects the leakage current density causing an enhancement in the interfacial polarization. The delocalization character of the charge carriers, influenced by impurities, plays a major role in the electrical polarization. The interfacial polarization contribution makes the remanent polarization and coercive field seem higher. We have discussed how an apparently single phase sample can lead to misleading interpretations of general physical properties such as magnetization, electrical polarization, and magnetic/elec-tric coercive fields which are important parameters in multiferroic systems. We emphasize that in order to study this system and to compare with others, samples must be prepared with extremely care.

Leia artigo completo aqui.

 

(12)  Nature of short-range order in the paramagnetic state of manganites

Journal of Alloys and Compounds 571, 21–24 (2013)

Fabian E.N. Ramirez, Elton Francisquini, Jose Antonio Souza

 

(11)  Magnetic, structural, and transport properties at very high temperature in manganites.

Journal of Magnetism and Magnetic Materials 324, 2011–2018 (2012)

Fabian Enrique Nima Ramirez, Fabio Furlan Ferreira, Wendel Andrade Alves, Jose Fernando Queiruga Rey, José Antonio Souza

 

(10)  Scaling behavior of nearly first order magnetic phase transitions

M. G. L. Ferreira and J. A. Souza

Journal of Physics: Condensed Matter v. 23, 226003 (2011)

 

(9)  Analysis of the critical behavior associated with the antiferromagnetic transitions of  LaMnO3 and CaMnO3

J. A. Souza, J. J. Neumeier, B. D. White and Yi-Kuo Yu

Physical Review B 81, 172410 (2010)

 

(8)  Magnetic, transport, and thermodynamic properties of CaMn_{2}O_{4} single crystals

D. White, J. A. Souza, C. Chiorescu, J. J. Neumeier, J. L. Cohn

Physical Review B, v. 79, 104427 (2009)

 

(7)  Polaron liquid-gas crossover at the orthorhombic-rhombohedral transition of manganites

 J. A. Souza, R. F. Jardim, R. Muccillo, E. Granado, and N. F. Oliveira Jr..

Physical Review B 78, 054411 (2008)

 

(6)  Magnetic signatures of ferromagnetic polarons in La0.7Ca0.3MnO3: Colossal Magnetoresistance is not a Griffiths Singularity

 J. A. Souza, J. J. Neumeier, and Yi-KuoYu

Physical Review B 78, 014436 (2008)

 

(5)  Dimensional Crossover in the Purple Bronze Li0.9Mo6O17

A. M. dos Santos, B. D. White, Yi-Kuo Yu, J. J. Neumeier, and J. A. Souza

Physical Review Letters 98, 266405 (2007)

 

(4)  Magnetic susceptibility and electrical resistivity of LaMnO3, CaMnO3 and La1-xSrxMnO3 (0 < x < 1) in the temperature range 300 – 900 K

J. A. Souza, J. J. Neumeier, R. K. Bollinger, B. McGuire, C. A. M. dos Santos, and H. Terashita

Physical Review B 76, 024407 (2007)

 

(3)  Effect of disorder on the thermodynamic phase transition in La0.7Ca0.3MnO3

 J. A. Souza, J. J. Neumeier, and R. F. Jardim

Physical Review B 75, 012412 (2007)

 

(2)  Method for Analyzing Second-Order Phase Transitions: Application to the Ferromagnetic Transition of a Polaronic System

J. A. Souza, Yi-Kuo Yu, J. J. Neumeier, H. Terashita, and R. F. Jardim.

Physical Review Letters 94, 207209 (2005)

 

(1)  Magnetoresistivity in the clustered state of La0.7-xYxCa0.3MnO3 manganites

J. A. Souza, and R. F. Jardim

Physical Review B 71, 054404 (2005)