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We investigate the dynamical behavior of quantum discord for the coupling qubits that placed in squeezed vacuum reservoir and initially in decoherence-free subspace (DFS). The results show that the DFS for resisting the effects from environmental decoherence and disentanglement is not the DFS of quantum discord. We also find that under certain conditions, the quantum discord and entanglement perform completely inversely versus the squeezed parameters. The quantum discord is controlled by the squeezed parameters, especially in the initial stage of the evolution, the bigger the parameter is, and the longer the time of initial death will be.

It is effective to constitute a hybrid qubit system by taking advantages of different types of qubits to overcome the effects of decoherence and achieve quantum information transport. We find that energy relaxation exists in the process of information exchange bewteen the hybrid qubits. Combining this kind of energy relaxation with the decoherence effects from external environment, quantum information transport of non-disentangled effect can be achieved in phase damping channel if the exchange decay rate and decoherence time satisfy certain constraint relations.