  Beyond the no-cloning theorem, the universal symmetric quantum cloning
machine was first addressed by Buzek and Hillery. Here, we realized the
one-to-two qubits Buzek-Hillery cloning machine with linear optical devices.
This method relies on the representation of several qubits by a single photon.
We showed that, the fidelities between the two output qubits and the original
qubit are both 5/6 (which proved to be the optimal fidelity of one-to-two
qubits universal cloner) for arbitrary input pure states.
