Abstract
Scanning magnetic microscopy is a tool that has been used to map magnetic fields with good spatial resolution and field sensitivity. This technology has great advantages over other instruments; for example, its operation does not require cryogenic technology, which reduces its operational cost and complexity. Here, we presented a spatial domain technique based on an equivalent layer approach for processing the data set produced by magnetic microscopy. This approach estimated a magnetic moment distribution over a fictitious layer composed by a set of dipoles located below the observation plane. For this purpose, we formulated a linear inverse problem for calculating the magnetic vector and its amplitude. Vector field maps are valuable tools for the magnetic interpretation of samples with a high spatial variability of magnetization. These maps could provide comprehensive information regarding the spatial distribution of magnetic carriers. In addition, this approach might be useful for characterizing isolated areas over samples or investigating the spatial magnetization distribution of bulk samples at the micro and millimeter scales. This technique could be useful for many applications that require samples that need to be mapped without a magnetic field at room temperature, including rock magnetism.
Highlights
Rock magnetism studies seek to retrieve information regarding primordial magnetic fields in terrestrial and extraterrestrial geological materials by analyzing their remanence magnetizations [1,2].Even if these materials may hold this magnetic information for millions or even billions of years, Materials 2019, 12, 4154; doi:10.3390/ma12244154 www.mdpi.com/journal/materialsMaterials 2019, 12, 4154 the record of the oldest magnetic fields is commonly obliterated by other magnetic records acquired during the geological history of these materials [3]
We could map the remanent fields of magnetic nanoparticles produced by laser ablation that have very small diameters. This type of magnetic map and magnetic moment obtained by magnetic microparticle scanning microscopy might be important for a number of applications, such as in vitro and in vivo studies
In order to estimate the other magnetic field components, we used a layer composed of M dipoles with unit volume, all of them positioned at a constant depth of z = h
Summary
Rock magnetism studies seek to retrieve information regarding primordial magnetic fields in terrestrial and extraterrestrial geological materials by analyzing their remanence magnetizations [1,2]. When the magnetic history is uncertain and complex, e.g., meteoritic magnetizations, the bulk magnetic measurements cannot archive each magnetic component [2] To overcome these constraints, high precision magnetometer devices have been developed in the last decade [4]. Most scanning magnetic microscopes require a cryogenic system, which greatly increases operating and maintenance costs, making them unviable for most low-cost laboratories Besides the cost, another problem related to magnetic microscopy lies in the elimination of some ambiguities inherent in this kind of measurements [7]. The microscope was equipped with commercial Hall-effect sensors, as shown in
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
