State transfer in intrinsic decoherence spin channels

S. V. Mousavi

曾天海, 邵彬, 邹健

Rahime Sufiani, Pedram, A.

By considering distance-regular graphs as spin networks, we investigate the state transfer fidelity in this class of networks. The effect of environment on the dynamics of state transfer is modeled using Milburn's intrinsic decoherence [G. J. Milburn, Phys. Rev. A 44, 5401 (1991)]. We consider a particular type of spin Hamiltonians which are extended version of those of Christandl et al [Phys. Rev. A 71, 032312 (2005)]. It is shown that decoherence destroys perfect communication channels. Using optimal coupling strengths derived by Jafarizadeh and Sufiani [Phys. Rev. A 77, 022315 (2008)], we show that destructive effect of environment on the communication channel increases by increasing the decoherence rate, however the state transfer fidelity reaches a steady value as time approaches infinity which is independent of the decoherence rate. Moreover, it is shown that for a given decoherence rate, the fidelity of transfer decreases by increasing the distance between the sender and the receiver.

Youssef Khedif, R. Muthuganesan

Tian-Hai Zeng, Shao Bin, Zou Jian

Considering Milburn's intrinsic decoherence effect on quantum communication through a spin chain, we show that the transfer quality for quantum state and entanglement will obviously decrease with the increasing intrinsic decoherence rate. Some odd chains are much higher than even ones for the state transfer efficiency. The state transfer of a long chain is very sensitive to the intrinsic decoherence, which turns out to be an obstacle for information transport.

D. X. Kong, An Min Wang