  Weyl semimetals are a topological phase of matter that have drawn recent
interest and have been suggested as a possible phase of the pyrochlore
irridates, among other materials. Here, we compute the magneto-optical response
of an isolated Weyl point. We find that the conductivity is a series of
asymmetric peaks lying on top of a linear background. We find additional
features in the conductivity that are explained by the underlying Landau level
structure. We show that weak disorder tends to blur out the peaks, but they
still show up as measurable oscillations on a linear background.
