  We study the ground-state phase diagram of a Bose-Fermi mixture loaded in a
one-dimensional optical lattice by computing the ground-state fidelity and
quantum entanglement. We find that the fidelity is able to signal quantum phase
transitions between the Luttinger liquid phase, the density-wave phase, and the
phase separation state of the system; and the concurrence can be used to signal
the transition between the density-wave phase and the Ising phase.
