A portable instrument for non-contact giant magnetoresistance measurements utilizing the magnetorefractive effect and infrared fibres

Tomas Stanton, Marian Vopsaroiu, Sarah M. Thompson

Research output: Contribution to journalArticlepeer-review


A portable, low-cost instrument is presented capable of non-contact giant magnetoresistance (GMR) measurements through correlation with the magnetorefractive effect. Each component has been optimized for signal-to-noise ratio, portability and economy. The final design incorporates a pulsable thin-film infrared emitter which floods the surface of the sample providing reflected radiation focused by a lens into an infrared transmitting fibre. This shields the signal and transports it to a lithium tantalate pyroelectric detector. The measurements are performed at 5 Hz, allowing phase sensitive discrimination to reduce noise levels. The instrument is tested on a CoFe/Cu GMR multilayer and its response demonstrated to compare very favourably with larger more expensive instruments providing new opportunities for the remote sensing of GMR.

Original languageEnglish
Article number125701
Pages (from-to)-
Number of pages7
JournalMeasurement Science and Technology
Issue number12
Publication statusPublished - Dec 2008


  • giant magnetoresistance
  • GMR
  • magnetorefractive effect
  • MRE
  • infrared

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