  We study numerically the mean access times for random walks on hybrid
disordered structures formed by embedding scale-free networks into regular
lattices, considering different transition rates for steps across lattice bonds
($F$) and across network shortcuts ($f$). For fast shortcuts ($f/F\gg 1 $) and
low shortcut densities, traversal time data collapse onto an universal curve,
while a crossover behavior that can be related to the percolation threshold of
the scale-free network component is identified at higher shortcut densities, in
analogy to similar observations reported recently in Newman-Watts small-world
networks. Furthermore, we observe that random walk traversal times are larger
for networks with a higher degree of inhomogeneity in their shortcut
distribution, and we discuss access time distributions as functions of the
initial and final node degrees. These findings are relevant, in particular,
when considering the optimization of existing information networks by the
addition of a small number of fast shortcut connections.
