  The time evolution of a wave packet is a tool to detect topological phase
transitions in two-dimensional Dirac materials, such as graphene and silicene.
Here we extend the analysis to HgTe/CdTe quantum wells and study the evolution
of their electron current wave packet, using 2D effective Dirac Hamiltonians
and different layer thicknesses. We show that the two different periodicities
that appear in this temporal evolution reach a minimum near the critical
thickness, where the system goes from normal to inverted regime. Moreover, the
maximum of the electron current amplitude changes with the layer thickness,
identifying that current maxima reach their higher value at the critical
thickness. Thus, we can characterize the topological phase transitions in terms
of the periodicity and amplitude of the electron currents.
