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.
@article{arxiv.1305.2798,
title = {Individual Addressing in Quantum Computation through Spatial Refocusing},
author = {Chao Shen and Zhe-xuan Gong and Luming Duan},
journal= {arXiv preprint arXiv:1305.2798},
year = {2013}
}