Spin waves are the elementary excitations of any magnetic material and play an essential role in all magnetic dynamics, for example in the flipping of a bit on a hard disk. In Nature Materials, Spinelli et al. of the Otte Lab report the observation of individual spin waves in a self-built magnetic bit of only 6 iron atoms. Not only can they discern standing waves of various wavelengths for different energies in our bit; they can also study the switching behaviour of the bit and identify the role of the spin waves in the switching process.
More information can be found in the News & Views article, written by Rohart and Rodary, that accompanies the paper.
Impression of different spin wave modes in a six atom chain, driven at low (top) and higher energy (bottom).