Abstract
We introduce an approach to quantum cloning based on spin networks and we demonstrate that phase covariant cloning can be realized using no external control but only with a proper design of the Hamiltonian of the system. In the cloning we find that the model saturates the value for the fidelity of the optimal cloner and gives values comparable to it in the general case. We finally discuss the effect of external noise. Our protocol is much more robust to decoherence than a conventional procedure based on quantum gates.
- Received 11 February 2004
DOI:https://doi.org/10.1103/PhysRevA.70.062308
©2004 American Physical Society