  We present numerical evidence that the spin-1/2 Heisenberg model on the
two-dimensional checkerboard lattice exhibits several magnetization plateaux
for m=0, 1/4, 1/2 and 3/4, where m is the magnetization normalized by its
saturation value. These incompressible states correspond to somehow similar
valence-bond crystal phases that break lattice symmetries, though they are
different from the already established plaquette phase for m=0. Our results are
based on Exact Diagonalization as well as Density Matrix Renormalization Group
large-scale simulations, and interpreted in terms of simple trial
wavefunctions.
