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The continuous-variable (CV) entanglement between two mesoscopic Josephson junctions is studied and the time-dependent characteristic function in Wigner representation for the Josephson junction subsystem driven by a single-mode thermal field is analytically obtained. It is found that an initial lowest energy state of the junction subsystem can evolve into a two-mode entangled Gaussian state through the interaction with the thermal radiation field. Furthermore, we investigate the influence of the temperature on the entanglement of the junctions and find that the CV entanglement of the two junctions shows the critical behavior with respect to the temperature.

We consider a composite system of two remote mesoscopic Josephson junctions interacting locally with a two-mode non-classical cavity field and investigate entanglement transfer from a bipartite continuous-variable (CV) system to a pair of localized mesoscopic Josephson junctions. We obtain analytically the time-dependent characteristic functions in the Wigner representation for the two CV subsystems, where two cases are considered for the zero and finite temperatures. Furthermore, we analyse the influences of the temperature on the period recovery of the entanglement.

We investigate the effect of phase shift on the entanglement transfer in two parallel 1D spin chains. We calculate the concurrence, measures for two-qubit entanglement, as a function of time. We find the maximum achievable entanglement in the cases with and without phase shift. Although the entanglement transfer becomes slow in most cases with phase shift, the significant enhancement of the maximum achievable entanglement is obtained which suggests its potential usefulness in quantum information processing.

We investigate the entanglement transfer in a four-qubit system and calculate the concurrence between any two qubits in different initial states. We show that both the pure entangled state and mixed entangled state can be transferred. For some special coupling constants and some evolution time, entanglement can be completely transferred from one pair particles to another.

We investigate the entanglement transfer in two parallel 1D spin chains of a quantum spin network, and show that the perfect entanglement transfer can be realized at some special times. In addition, the so-called `sudden death' phenomenon of entanglement is found in the spin network system.