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Use of dynamical coupling for improved quantum state transfer

A. O. Lyakhov·C. Bruder
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Abstract

We propose a method to improve quantum state transfer in transmission lines. The idea is to localize the information on the last qubit of a transmission line, by dynamically varying the coupling constants between the first and the last pair of qubits. The fidelity of state transfer is higher then in a chain with fixed coupling constants. The effect is stable against small fluctuations in the system parameters.

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A. O. Lyakhov, C. Bruder. 2006-09-29. Use of dynamical coupling for improved quantum state transfer. https://doi.org/10.1103/physrevb.74.235303

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