We report the experimental demonstration of a controlled-NOT (CNOT) quantum logic gate between motional and internal state qubits of a single ion where, as opposed to previously demonstrated gates, the conditional dynamics depends on the extent of the ion's wave-packet. Advantages of this CNOT gate over one demonstrated previously are its immunity from Stark shifts due to off-resonant couplings and the fact that an auxiliary internal level is not required. We characterize the gate logic through measurements of the post-gate ion state populations for both logic basis and superposition input states, and we demonstrate the gate coherence via an interferometric measurement.
@article{arxiv.quant-ph/0208180,
title = {Experimental demonstration of a controlled-NOT wave-packet gate},
author = {B. DeMarco and A. Ben-Kish and D. Leibfried and V. Meyer and M. Rowe and B. M. Jelenković and W. M. Itano and J. Britton and C. Langer and T. Rosenband and D. J. Wineland},
journal= {arXiv preprint arXiv:quant-ph/0208180},
year = {2016}
}