Physics NotePublished
Implementation and Applications of a 3D-sensitive Giant Magnetoresistance (GMR) Sensor
Sarah S. Rabelo; M.F. Lopes; S.B. Belmonte; I. S. Oliveira
Publication details
- Authors
- Sarah S. Rabelo; M.F. Lopes; S.B. Belmonte; I. S. Oliveira
- Type
- Physics Note
- Status
- Published
- Publication date
- 27/12/2005
- Description
- We report the implementation and applications of a GMR commercial magnetic sensor, capable of measuring simultaneously the three cartesian components of a magnetic field, either DC or AC. After calibration procedure, basic tests are made by mapping the magnetic field around a small solenoid. The response of the sensor to a vibrating magnetic sample is then studied in various si\-tu\-ati\-ons of resonance: (a) continuous vibrating sample; (b) sinusoidal amplitude modulated motion; (c) squared amplitude modulated motion and (d) modulated pulsed signal. This last experiment is rather similar to what is done in the well known technique of Nuclear Magnetic Resonance (NMR). The sensor response in this case resembles the Free Induction Decay, the signal observed in usual NMR experiments. The Fourier transform of such signals reveals the response of different vibrating modes of the system. The high sensitivity of the sensor is tested for mechanical noise, what entitles it to be used in various applications. Computer interfacing is made through the parallel port, and experiments were automated through a LabVIEW routine. Details on the built circuitry for reading from and writing to the sensor are also presented.
- Year
- 2005
- Number
- CBPF-NF-017/05
- Linked to a thesis
- No
- Linked to a grant
- No