  We study the ground state quantum phase transition by means of entanglement
in the one-dimensional asymmetric Hubbard model with open boundary condition.
The local entanglement between the middle two sites and the rest of the system,
and the block entanglement between the left and right portions of the system,
are calculated using the density-matrix renormalization group (DMRG) method. We
find that the entanglement shows interesting scaling and singular behavior
around the phase transition line.
