TITLE

Number sensitive detection and direct imaging of dipolar coupled magnetic nanoparticles by tunnel magnetoresistive sensors

AUTHOR(S)
Albon, C.; Weddemann, A.; Auge, A.; Meißner, D.; Rott, K.; Jutzi, P.; Hütten, A.
PUB. DATE
October 2009
SOURCE
Applied Physics Letters;10/19/2009, Vol. 95 Issue 16, p163106
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The suitability of magnetic tunnel junctions for the detection of magnetic nanoparticles is related to their scalability onto the nanoscale size regime without a significant loss of sensitivity. Elliptically shaped MgO based tunnel magnetoresistance sensors are used to provide a sharp detection of 14 nm Co nanoparticles. The measured signal is related to the degree of coverage of the sensor area by a nanoparticle layer. Moreover, the nanoparticles magnetostatic interaction on the sensor surface is clearly distinguished by the presence of a coercitive field in the detected signal. Experimentally obtained results are compared to theoretical models.
ACCESSION #
44837262

 

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