quantum telecloning. We show how the scheme can be implemented in a realistic system of atomic spin qubits in an optical lattice. Error analysis shows that high-fidelity state engineering is possible for

N\ensuremath{\sim}O(100)

spins in the presence of decoherence. The scheme can also prepare a resource state for the secret sharing protocol and for the construction of the large-scale Affleck-Kennedy-Lieb-Tasaki state.

DOI: 10.1103/physreva.84.032337

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N

-pumped spin qubits realizes the ideal resource for the

1\ensuremath{\rightarrow}\frac{N}{2}

N\ensuremath{\sim}O(100)

spins in the presence of decoherence. The scheme can also prepare a resource state for the secret sharing protocol and for the construction of the large-scale Affleck-Kennedy-Lieb-Tasaki state.