title: Single core-shell nanoparticle probes for non-invasive magnetic force microscopy.
abstract: We present an easy, fast and reliable method for the preparation of magnetic force microscopy (MFM) probes based on single Co nanoparticles (NPs). Due to their dipolar character, these magnetic probes open up a new approach for quantitative and non-invasive MFM measurements on the nanometer length scale. To guarantee long-term stability of these tips under ambient conditions, an ultrathin protecting Au shell was grown around the Co NPs through photochemical deposition. Single magnetic particles were firmly attached to standard silicon AFM tips using bifunctional self-assembling molecules. Such probes were tested on longitudinal magnetic recording media and compared to the results as recorded with conventional thin-film MFM tips. Easy data interpretation of the magnetic nanoparticle probes in a point dipole model is shown. Our nanoparticle tips provide excellent endurance for MFM recording, enable non-invasive probing while maintaining a high sensitivity, resolution, and reproducibility.
authors.affiliation: Institut für Angewandte Photophysik, Technische Universität Dresden, George-Bähr-Straße 1, D-01069 Dresden, Germany.
authors.forename: Tino
authors.initials: T
authors.lastname: Uhlig
authors.forename: Ulf
authors.initials: U
authors.lastname: Wiedwald
authors.forename: Axel
authors.initials: A
authors.lastname: Seidenstücker
authors.forename: Paul
authors.initials: P
authors.lastname: Ziemann
authors.forename: Lukas M
authors.initials: LM
authors.lastname: Eng
mesh_terms: D003035:Cobalt / Q000737:chemistry; D060328:Magnetic Phenomena; D018625:Microscopy, Atomic Force / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D015203:Reproducibility of Results
chemical_list: D003035:Cobalt