I'll discuss spin waves and micromagnetism. I'll then discuss my work on a particularly simple magnonic crystal which supports some interesting excitations including graphene-analog spin waves. The lowest 9 bands turn out to be understandable from a tight-binding-like picture. To demonstrate the large degree of tunability the system has, I use it to realize some cool states like massless Jackiw-Rebbi domain wall spin waves and, in another part of the parameter space, chiral edge states in a magnonic Chern "insulator." Aside from fundamental interest, these states may actually be helpful in some rf devices.
