Magnetic attraction

This array of nanomagnets, as seen by a magnetic force microscope, could form the basis of the next generation of magnetic data storage. Made by scientists at Cornell University, US, each magnet is a cobalt dot on a silicon surface. The researchers have read the orientation of individual magnets using a magnetic force microscope. The above is a false-colour image of the magnetic fields rather than the actual dots of magnetic material. White areas indicate magnetic field lines coming up out of the plane of the image, and dark areas indicate field lines going down into the plane. Each magnet appears as a dipole with a pole at each end and field line curving up and around between the poles. Here, all the dipoles are aligned in the same direction except one.