  We propose that the dynamical axion field can be realized in a magnetic
topological insulator superlattice or a topological paramagnetic insulator. The
magnetic fluctuations of these systems produce a pseudoscalar field which has
an axionic coupling to the electromagnetic field, and thus it gives a
condensed-matter realization of the axion electrodynamics. Compared to the
previously proposed dynamical axion materials where a long range
antiferromagnetic order is required, the systems proposed here have the
advantage that only a uniform magnetization or a paramagnetic state is needed
for the dynamic axion. We further propose several experiments to detect such a
dynamical axion field.
