Magnetic materials are important components in many electronic systems. In order to optimize a system with magnetic materials, one must understand the magnetic properties of the material used. At Imego´s electromagnetic labs we can perform both static and dynamic magnetic characterization of all sorts of magnetic materials and magnetic sensor systems. We have several years of experience with magnetic materials, magnetic properties and magnetic characterization. We can help external customers to choose the right magnetic-particle system or the magnetic material in their applications as well as help with the magnetic characterization.
Static magnetic characterization
Static magnetic measurement gives the equilibrium magnetization versus magnetic field, temperature and time. With it, we can specify the magnetization processes in a magnetic particle system or magnetic material. For instance, the total magnetization curve versus field at constant temperature provides very good process control in the manufacturing of well-defined magnetic particle systems.
Dynamic magnetic characterization
The dynamic magnetic properties give information on how fast magnetization is building up in the material. Different types of magnetization processes can be detected with dynamic magnetic measurements such as magnetization reversal in magnetic single domains (Néel relaxation), random rotation of particles containing thermally blocked single domains (Brownian relaxation) and domain-wall motion that occur in polydomain materials. All of these magnetization processes create a specific pattern in the dynamic magnetic properties which are seen in, for instance, the magnetic AC susceptibility. AC susceptometry has a wide area of application from magnetic-particle manufacturing to measuring soils in geophysical applications.
By detecting the Brownian relaxation of particles we are able to determine the size distribution of the particles. With the same method, we can study the clustering of the particles and follow the binding reactions of different substances to the surface of the particles. We quantify the adsorption of antibodies onto suitably prepared magnetic nanoparticles. This allows us to extend applications of the method to label-free medical diagnostics, bacteria detection and at-line optimization of protein production.