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Quantum Communication Through a Spin-Ring with Twisted Boundary Conditions

S. Bose·B. -Q. Jin·V. E. Korepin
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Abstract

We investigate quantum communication between the sites of a spin-ring with twisted boundary conditions. Such boundary conditions can be achieved by a flux through the ring. We find that a non-zero twist can improve communication through finite odd numbered rings and enable high fidelity multi-party quantum communication through spin rings (working near perfectly for rings of 5 and 7 spins). We show that in certain cases, the twist results in the complete blockage of quantum information flow to a certain site of the ring. This effect can be exploited to interface and entangle a flux qubit and a spin qubit without embedding the latter in a magnetic field.

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S. Bose, B. -Q. Jin, V. E. Korepin. 2004-12-24. Quantum Communication Through a Spin-Ring with Twisted Boundary Conditions. https://doi.org/10.1103/physreva.72.022345

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