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arXiv · 1305.2798

Individual Addressing in Quantum Computation through Spatial Refocusing

Chao Shen·Zhe-xuan Gong·Luming Duan
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Abstract

Separate addressing of individual qubits is a challenging requirement for scalable quantum computation, and crosstalk between operations on neighboring qubits remains as a significant source of noise for current experimental implementation of multi-qubit platforms. We propose a scheme based on spatial refocusing from interference of several coherent laser beams to significantly reduce the crosstalk noise for any type of quantum gates. A general framework is developed for the spatial refocusing technique, in particular with practical Gaussian beams, and we show under typical experimental conditions, the crosstalk-induced infidelity of quantum gates can be reduced by several orders of magnitude with a moderate cost of a few correction laser beams.

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Chao Shen, Zhe-xuan Gong, Luming Duan. 2013-11-07. Individual Addressing in Quantum Computation through Spatial Refocusing. https://doi.org/10.1103/physreva.88.052325

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