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arXiv · 1106.3502

Duplex quantum communication through a spin chain

Zhao-Ming Wang·C. Allen Bishop·Yong-Jian Gu·Bin Shao
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Abstract

Data multiplexing within a quantum computer can allow for the simultaneous transfer of multiple streams of information over a shared medium thereby minimizing the number of channels needed for requisite data transmission. Here, we investigate a two-way quantum communication protocol using a spin chain placed in an external magnetic field. In our scheme, Alice and Bob each play the role of a sender and a receiver as two states cos({\theta}1/2)|0> + sin({\theta}1/2)exp(i{\phi}1)|1>, cos({\theta}2/2)|0> + sin({\theta}2/2)exp(i{\phi}2)|1> are transferred through one channel simultaneously. We find that the transmission fidelity at each end of a spin chain can usually be enhanced by the presence of a second party. This is an important result for establishing the viability of duplex quantum communication through spin chain networks.

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Zhao-Ming Wang, C. Allen Bishop, Yong-Jian Gu, Bin Shao. 2011-06-17. Duplex quantum communication through a spin chain. https://doi.org/10.1103/physreva.84.022345

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