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DOE OSTI · 22051278

Quantum correlation transfer through two parallel XXZ spin chains with phase shift control

Jian, Zhang·Bin, Shao·Benqiong, Liu·Jian, Zou·Qianshu, Li·Lianao, Wu
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Abstract

Transmitting quantum states and entanglement through quantum channels is one of the key requirements for the development of quantum computation. Quantum discord has received much attention in quantum computation. We transfer quantum discord through two parallel XXZ spin chains with phase shift. The maximum discord can be enhanced by the phase shift. It will take more time to obtain an enhanced maximum discord in some cases, but for other cases, both the maximum and speed are enhanced by the phase shift. In the thermodynamic limit, the effect of the phase shift disappears and the maximum discord exponentially decays with increasing of the receiving position. Our results on spin chains are generalized to a family of linear Hamiltonians.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSHAMILTONIANSPHASE SHIFTQUANTUM COMPUTERSQUANTUM ENTANGLEMENTQUANTUM STATESSPIN

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Jian, Zhang, Bin, Shao, Benqiong, Liu, Jian, Zou, Qianshu, Li, Lianao, Wu. 2011-07-15. Quantum correlation transfer through two parallel XXZ spin chains with phase shift control. https://doi.org/10.1103/physreva.84.012327

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