SCHEME FOR IMPLEMENTATION OF THE OPTIMAL 1 → 2 UNIVERSAL QUANTUM CLONING WITH SQUID QUBITS IN A CAVITY VIA A RAMAN TRANSITION

We propose a scheme to realize the optimal 1 -> 2 universal quantum cloning (UQC) in 2-dimension with superconducting quantum-interference device (SQUID) qubits in a microwave cavity. In our scheme, three-SQUIDs are fixed in a microwave cavity via a Raman transition for their manipulation. Using this method, no transfer of quantum information between the SQUIDs and the cavity is required, the cavity field is only virtually excited and thus the cavity decay is suppressed during the cloning process. Furthermore, our scheme only requires using the two lower flux states of the SQUID system and the excited state is not excited. So the effect of decoherence based on the levels of the SQUID system is possible to minimize.