Single core-shell nanoparticle probes for non-invasive magnetic force microscopy.

Area of Science:

• Materials Science
• Nanotechnology
• Surface Science

Background:

• Magnetic Force Microscopy (MFM) is crucial for nanoscale magnetic imaging.
• Conventional MFM tips face limitations in quantitative and non-invasive measurements.
• Developing stable, high-performance MFM probes is an ongoing challenge.

Purpose of the Study:

• To present a novel, facile method for preparing MFM probes utilizing single cobalt nanoparticles (NPs).
• To enable quantitative and non-invasive MFM measurements at the nanometer scale.
• To enhance the stability, sensitivity, resolution, and reproducibility of MFM probes.

Main Methods:

• Preparation of MFM probes using single cobalt nanoparticles (Co NPs).
• Photochemical deposition of an ultrathin gold (Au) shell for stability.
• Attachment of Co NPs to silicon AFM tips via self-assembling molecules.
• Testing and comparison with conventional thin-film MFM tips on magnetic recording media.

Main Results:

• Demonstrated a simple, fast, and reliable method for Co NP-based MFM probe preparation.
• Achieved long-term stability of magnetic probes under ambient conditions.
• Showcased easy data interpretation using a point dipole model for nanoparticle probes.
• Verified high sensitivity, resolution, reproducibility, and excellent endurance for MFM recording.

Conclusions:

• Co NP-based MFM probes offer a new approach for quantitative and non-invasive nanoscale magnetic measurements.
• The developed probes provide superior performance characteristics compared to conventional MFM tips.
• This method facilitates advanced MFM applications in materials characterization and data storage research.