Researchers at NIST have developed a new method to measure the magnetic properties of nanoparticles using magnetic bubbles. The technique involves expanding tiny magnetic bubbles on a sensitive film to visible sizes, allowing detection with an optical microscope. This method is fast, economical, and can be performed at room temperature, making it practical for manufacturers to measure and control the properties of magnetic nanoparticles for various applications.
The new technique allows researchers to track changes in the magnetic orientation of individual nanoparticles in real-time. By applying an external magnetic field, the team could expand the bubbles to visible sizes, revealing the magnetic orientation of each nanoparticle. This enabled precise measurements of the magnetic stability of individual nanoparticles, which had previously been challenging to determine.
The method’s advantages over existing techniques include its speed, convenience, and ability to operate at room temperature. This makes it well-suited for studying the behavior of magnetic nanoparticles in real-time, such as during the assembly and operation of magnetic microsystems. The study represents NIST’s ongoing efforts to improve the measurement capabilities of optical microscopes, an instrument widely available in most labs.
Keywords: Magnetic Nanoparticles, Dzyaloshinskii-Moriya interaction, Nanoscale Magnetic Fields, Coercive Field, Magnetic Bubbles
