3. Examples of magnetic nanostructures

There are 4 categories of magnetic nanostructures:

• massive materials that are structurally nanostructured but whose general properties are well described on the macroscopic scale;

• thin films or layers, including multilayers, with a thickness of a few nanometers;

• structures lithographed (etching, photolithography) or self-assembled by deposition of atoms or molecules;

• nanoparticles derived from organic or inorganic chemistry (organometallics, living organisms, etc.).

To illustrate the considerable variety of form and behavior that can be encountered in the field of nanostructures, three very different examples are now discussed in more detail: thin films, nanowires and molecular aggregates.