  he thermal entanglement is generated by weakly interacting atoms with an
isotropic spin-1 chain. The decoherence of the entanglement is mainly
investigated. The effective Hamiltonian is analytically obtained by the
approximation method of perturbation. The scaling behavior of the effective
coupling is numerically illustrated by the exact diagonalization. It is found
out that the decay of the entanglement is slow in the case of non interacting
spins. The long-distance thermal entangled states can be used as the noisy
channel for the achievement of the quantum teleportation.
