  Majorana fermions were originally proposed as elementary particles acting as
their own antiparticles. In recent years, it has become clear that Majorana
fermions can instead be realized in condensed-matter systems as emergent
quasiparticles, a situation often accompanied by topological order. Here we
propose a physical system which realizes Landau levels - highly degenerate
single-particle states usually resulting from an orbital magnetic field acting
on charged particles - for Majorana fermions. This is achieved in a variant of
a quantum spin system due to Kitaev which is distorted by triaxial strain. This
strained Kitaev model displays a spin-liquid phase with charge-neutral
Majorana-fermion excitations whose spectrum corresponds to that of Landau
levels, here arising from a tailored pseudo-magnetic field. We show that
measuring the dynamic spin susceptibility reveals the Landau-level structure by
a remarkable mechanism of probe-induced bound-state formation.
