Effect of spin-valve sensor magnetostatic fields on nanobead detection for biochip applications

Ferreira H.A., Feliciano N., Graham D.L., Freitas P.P.
INESC-microsystems and Nanotechnologies, Lisbon, Portugal; Physics Department, Instituto Superior T́cnico, UTL, Lisbon, Portugal

Abstract: Spin valves are being used in biochip applications via the detection of biomolecular recognition using magnetic nanoparticles as labels. The magnetic moment of the labels and the sensor response depend on the magnetic fields involved. A calculation based on an external magnetizing field, incorporating the contribution from the magnetostatic fields created by the free and pinned layers of the sensor and the field due to the sensing current, showed that these fields are important. Experimental detection signals of high particle numbers agree with the model, showing that reasonable detection signals are possible even in the absence of an external field. © 2005 American Institute of Physics.

Year: 2005
Source title: Journal of Applied Physics
Volume: 97
Issue: 10
Art. No.: 10Q904
Page : 1-3
Cited by: 9
Link: Scorpus Link
Document Type: Article
Source: Scopus
Authors with affiliations:

1. Ferreira, H.A., INESC-microsystems and Nanotechnologies, Lisbon, Portugal, Physics Department, Instituto Superior T́cnico, UTL, Lisbon, Portugal
2. Feliciano, N., INESC-microsystems and Nanotechnologies, Lisbon, Portugal
3. Graham, D.L., INESC-microsystems and Nanotechnologies, Lisbon, Portugal
4. Freitas, P.P., INESC-microsystems and Nanotechnologies, Lisbon, Portugal, Physics Department, Instituto Superior T́cnico, UTL, Lisbon, Portugal

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