Lopes, A. M. L., Araujo, J. P., Amaral, V. S., Correia, J. G., Tomioka, Y., Tokura, Y.
A detailed study of the electric field gradient (EFG) across the Pr1-xCaxMnO3 phase diagram and its temperature dependence is given. Clearly, distinct EFG behaviours for samples outside/inside the...
Nanoscopic processes of Current Induced Switching in thin tunnel junctions (2006)
Ventura, J., Araujo, J. P., Sousa, J. B., Liu, Y., Zhang, Z., Freitas, P. P.
In magnetic nanostructures one usually uses a magnetic field to commute between two resistance (R) states. A less common but technologically more interesting alternative to achieve R-switching is to...
Domain imaging, MOKE and magnetoresistance studies of CoFeB films for MRAM applications (2005)
Teixeira, J. M., Silva, R. F. A., Ventura, J., Pereira, A. M., Carpinteiro, F., Araujo, J. P., ...
We present a detailed study on domain imaging, Kerr effect magnetometry (MOKE) and magnetoresistance (MR), for a series of 20 nm Co$_{73.8}$Fe$_{16.2}$B$_{10}$ thin films, both as-deposited...
Teixeira, J. M., Silva, R. F. A., Ventura, J., Pereira, A., Araujo, J. P., Amado, M., ...
A MOKE magnetometry unit simultaneously sensitive to both in-plane magnetization components, based on an intensity differential detection method, allows us to observe the uniaxial anisotropy...
Lopes, A. M. L., Araujo, J. P., Ramasco, J. J., Rita, E., Amaral, V. S., Correia, J. G., ...
In this work, we report an atomic scale study on the ferromagnetic insulator manganite LaMnO$_{3.12}$ using $\gamma-\gamma$ PAC spectroscopy. Data analysis reveals a nanoscopic transition from an...
Ion beam studies of single crystalline manganite thin films (2004)
Alves, E., Marques, C., Amaral, V. S., Araujo, J. P., Cristiani, G., ...
Colossal magneto resistive manganites are oxide materials where the magnetic interactions and the electrical properties are mainly controlled by the Mn valence ratio (+3/+4). For thin films these...
Influence of charge ordering on the magnetocaloric effect of (Pr,Ca)MnO$_3$ manganites (2003)
Reis, M. S., Amaral, V. S., Araujo, J. P., Tavares, P. B., Gomes, A. M., Oliveira, I. S.
In the present work we analyze the influence of the charge-ordering on the magnetocaloric effect of Pr$_{1-x}$Ca$_x$MnO$_3$ manganites. The results for the samples with $x
Magnetic phase diagram for a non-extensive system: Experimental connection with manganites (2003)
Reis, M. S., Araujo, J. P., Amaral, V. S., Oliveira, I. S.
In the present paper we make a thorough analysis of a classical spin system, within the framework of Tsallis nonextensive statistics. From the analysis of the generalized Gibbs free energy, within...
Magnetic behavior of a non-extensive S-spin system: possible connections to manganites (2002)
Reis, M. S., Araujo, J. P., Amaral, V. S., Lenzi, E. K., Oliveira, I. S.
We analyzed the magnetic behavior of a S-spin system within framework of the Tsallis nonextensive statistics, employing the normalized approach. Unusual properties on magnetization, entropy and...