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Unmodulated spin chains as universal quantum wires

Antoni Wojcik·Tomasz Luczak·Pawel Kurzynski·Andrzej Grudka·Tomasz Gdala·Malgorzata Bednarska
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Abstract

We study a quantum state transfer between two qubits interacting with the ends of a quantum wire consisting of linearly arranged spins coupled by an excitation conserving, time-independent Hamiltonian. We show that if we control the coupling between the source and the destination qubits and the ends of the wire, the evolution of the system can lead to an almost perfect transfer even in the case in which all nearest-neighbour couplings between the internal spins of the wire are equal.

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Antoni Wojcik, Tomasz Luczak, Pawel Kurzynski, Andrzej Grudka, Tomasz Gdala, Malgorzata Bednarska. 2005-05-13. Unmodulated spin chains as universal quantum wires. https://doi.org/10.1103/physreva.72.034303

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