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Efficient quantum state transfer in spin chains via adiabatic passage

K. Eckert·O. Romero-Isart·A. Sanpera
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Abstract

We propose a method for quantum state transfer in spin chains using an adiabatic passage technique. Modifying even and odd nearest-neighbour couplings in time allows to achieve transfer fidelities arbitrarily close to one, without the need for a precise control of coupling strengths and timing. We study in detail transfer by adiabatic passage in a spin-1 chain governed by a generalized Heisenberg Hamiltonian. We consider optimization of the transfer process applying optimal control techniques. We discuss a realistic experimental implementation using cold atomic gases confined in deep optical lattices.

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K. Eckert, O. Romero-Isart, A. Sanpera. 2007-05-03. Efficient quantum state transfer in spin chains via adiabatic passage. https://doi.org/10.1088/1367-2630%2F9%2F5%2F155

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