Department of Physics;
Pontifícia Universidade Católica do Rio de Janeiro;
Rio de Janeiro;
Brazil;
Department of Earth;
Atmospheric;
and Planetary Sciences;
Massachusetts Institute of Technology;
Cambridge;
USA;
Centro Brasileiro de Pesquisas Físicas;
Rio de Janeiro;
Brazil;
Practical; Magnetometer; Hall; Sensor; Characterization; of; Magnetic; Materials;