Quantum state transfer through system-environment correlation

Quantum state transfer protocol based on system-environment correlation is studied. Different from that in protocol of quantum teleportation, in the present transfer protocol, parties do not share entangled state initially. The state factors are transmitted among parties through their common memory-environment. Explicitly, with the generation of system-environment correlation, state factors parameterized on the probe system can be transmitted to the environment by performing proper projective measurement on the probe system. Then after knowing the results of former measurements, other parties can estimate the state factors by preparing proper detectors that evolve with the memory environment for a proper period of time. In this regard, quantum state is transmitted among different parties through system-environment correlation. Since quantum decoherence appears along with the generation of system-environment correlation, using the present transfer protocol, one can transmit quantum state even after the characteristic time of quantum decoherence.