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arXiv · 0705.0312

Two-dimensional transport and transfer of a single atomic qubit in optical tweezers

J. Beugnon·C. Tuchendler·H. Marion·A. Gaetan·Y. Miroshnychenko·Y. R. P. Sortais·A. M. Lance·M. P. A. Jones·G. Messin·A. Browaeys·P. Grangier
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Abstract

Quantum computers have the capability of out-performing their classical counterparts for certain computational problems. Several scalable quantum computing architectures have been proposed. An attractive architecture is a large set of physically independant qubits, arranged in three spatial regions where (i) the initialized qubits are stored in a register, (ii) two qubits are brought together to realize a gate, and (iii) the readout of the qubits is performed. For a neutral atom-based architecture, a natural way to connect these regions is to use optical tweezers to move qubits within the system. In this letter we demonstrate the coherent transport of a qubit, encoded on an atom trapped in a sub-micron tweezer, over a distance typical of the separation between atoms in an array of optical traps. Furthermore, we transfer a qubit between two tweezers, and show that this manipulation also preserves the coherence of the qubit.

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J. Beugnon, C. Tuchendler, H. Marion, A. Gaetan, Y. Miroshnychenko, Y. R. P. Sortais, A. M. Lance, M. P. A. Jones, G. Messin, A. Browaeys, P. Grangier. 2007-05-02. Two-dimensional transport and transfer of a single atomic qubit in optical tweezers. https://doi.org/10.1038/nphys698

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