MOKE and MFM on magnetically coated nanofiber mats: Transferring well‐known methods to uncommon samples

Abstract

The hysteresis loops of magnetic samples can be measured by the magneto-optical Kerr effect (MOKE), while magnetic force microscopy (MFM) is used to depict domain walls or spatially resolved magnetization orientation in magnetic nanostructures or thin films. Both methods are commonly applied on thin films with a perfectly flat surface or on nanostructures. Here, we report MOKE and MFM measurements on a new class of magnetic materials, namely electrospun mats of randomly oriented nanofibers which influence the 30 nm Co coating layer, proving especially the MOKE method utilizable for rough surfaces. Possible interpretations of these first MOKE measurements on highly randomly structured magnetic layers are given.

Nanofibers are a matter of perspective: effects of methodology and subjectivity on diameter measurements

“…(c) AFM is oen used because it provides more information than mere imaging, such as topographical, mechanical, electrical, or magnetic properties. 20,35 Again, both pristine and coated bers were imaged by AFM. As we will see, it is, however, the least reliable method for diameter measurements.…”

“…17 Atomic force microscopy (AFM) is oen used to characterize nanober properties beyond mere morphology, such as magnetization, friction, or mechanical strength. [18][19][20][21] The micrographs are commonly analyzed manually using image analysis soware to determine diameter distributions. Some automated image analysis tools have been developed that allow for rapid batch analysis, e.g.…”

A Review of the Current State of Magnetic Force Microscopy to Unravel the Magnetic Properties of Nanomaterials Applied in Biological Systems and Future Directions for Quantum Technologies

“…Traditionally, MFM is capable of being combined with other magnetic bulk techniques such as MOKE, which enables ultrathin films of varying temperatures in vacuum conditions [ 341 ] or randomly oriented magnetic electrospun nanofibers to be studied [ 342 ]. Then, MFM measurements can be also aligned with TEM-based DPC techniques.…”

Optical Properties of Electrospun Nanofiber Mats

“…The authors also investigated the influence of diverse other ions or molecules on the change in the RLS spectra and found them to be negligible, i.e., that this optical sensor has a high selectivity towards sunitinib. Even more specialized sensing applications were reported for scattered reflection from magnetic nanofiber mats, usually referred to as D-MOKE (diffractive magneto-optical Kerr effect), where measurements along different angles of reflection were shown to contain information about the magnetism of a sample, which can be measured by measuring the rotation of the original linear polarization axis of the impinging laser beam [103,104].…”