  We show that using a slightly modified XX model for a spin-1/2 chain, one can
transmit almost perfectly a maximally entangled two-qubit state from one end of
the chain to the other one. This is accomplished without external fields or
modulation of the coupling constants among the qubits. We also show that this
strategy works for any size of the chain and is relatively robust to
imperfections in the coupling constants among the qubits belonging to the
chain. Actually, under certain scenarios of small disorder, we obtain better
results than those predicted by the optimal ordered and noiseless case.
