Development of a high precision absolute linear displacement sensor utilizing GMR spin-valves

Author

Miller, M.M. ; Lubitz, P. ; Prinz, G.A. ; Krebs, J.J. ; Edelstein, A.S. ; Cheng, S.F. ; Parsons, F.G.

Author_Institution

Naval Res. Lab., Washington, DC, USA

Volume

33

Issue

5

fYear

1997

fDate

9/1/1997 12:00:00 AM

Firstpage

3388

Lastpage

3390

Abstract

We describe the development of a novel linear displacement sensor utilizing Giant Magnetoresistance (GMR) elements. This device is based on the division of a magnetically soft layer of a spin valve device into two anti-parallel magnetic domains. The total resistance of the spin-valve varies linearly with displacement of the domain wall because of different resistances of the aligned and anti-aligned magnetic states of the spin-valve. Domain wall translation is achieved by the use of a magnetic wall “trap” generated by permanent magnets. Displacement is thus related directly to the device resistance

Keywords

displacement measurement; giant magnetoresistance; magnetic domain walls; magnetic sensors; magnetoresistive devices; GMR spin valve; giant magnetoresistance element; linear displacement sensor; magnetic domain wall trap; Coercive force; Giant magnetoresistance; Indexing; Magnetic devices; Magnetic domain walls; Magnetic domains; Magnetic materials; Magnetic sensors; Magnetic separation; Magnetic switching; Magnets; Permanent magnets; Sensor phenomena and characterization; Soft magnetic materials; Spin valves;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.617953

Filename

617953