Superparamagnets
Superparamagnets are a type of magnetic material that exhibit unique properties at the nanoscale. Unlike traditional magnets, which can retain their magnetization, superparamagnets do not have a permanent magnetic moment. Instead, they can quickly switch their magnetization direction in response to an external magnetic field, making them useful in various applications.
These materials are often composed of tiny magnetic nanoparticles, typically less than 20 nanometers in size. When these particles are small enough, thermal energy can overcome the magnetic interactions that would normally keep them aligned. This behavior is important in fields like data storage, biomedical applications, and magnetic resonance imaging (MRI).