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Bubble Magnetometry of Nanoparticle Heterogeneity and Interaction
Andrew L Balk1,2,3, Ian Gilbert1, Robert Ivkov4
1Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
Physical Review Applied
|October 4, 2019
Summary
We developed bubble magnetometry using nanomagnetic films to rapidly measure individual magnetic nanoparticles. This technique precisely analyzes magnetic properties and transitions in nanoparticle behavior.
Area of Science:
- Condensed Matter Physics
- Nanotechnology
- Materials Science
Background:
- Bubbles have historically served as transducers in particle physics.
- Nanomagnetic films offer a solid-state platform for novel sensing applications.
Purpose of the Study:
- To introduce and validate bubble domain magnetometry for measuring magnetic nanoparticles.
- To achieve high-throughput analysis of nanoparticle magnetic properties.
Main Methods:
- Utilizing bubble domains in nanomagnetic films as sensors for magnetic nanoparticles.
- Tuning nanomagnetic film properties, including Dzyaloshinskii-Moriya interaction and skyrmion states.
- Developing the technique on nickel-iron nanorods and iron-oxide nanoparticles.
Main Results:
- Demonstrated rapid determination of single nanoparticle magnetic orientation (sub-second) and hysteresis loop generation (seconds).
- Enabled precise statistical analysis of magnetic hysteresis in dispersed nanoparticles.
- Measured the transition from superparamagnetic to collective behavior in nanoparticle agglomerates.
Conclusions:
- Bubble magnetometry provides a practical and high-throughput method for characterizing magnetic nanoparticles.
- The technique is capable of assessing nanoparticle heterogeneity and interactions.
- This solid-state approach advances nanoparticle sensing and analysis capabilities.
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