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arXiv · 0810.2178

Simplified approach to generate controlled-NOT gates with single trapped ions for arbitrary Lamb-Dicke parameters

Miao Zhang·H. Y. Jia·L. F. Wei
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Abstract

For certain {\it specific} (or {\it"magic"}) Lamb-Dicke (LD) parameters, Monroe {\it et al} showed [Phys. Rev. {\bf A 55}, R2489 (1997)] that a two-qubit quantum operation, between the external and internal degrees of freedom of a single trapped ion, could be implemented by applying a single carrier laser pulse. Here, we further show that, such a two-qubit operation (which is equivalent to the standard CNOT gate, only apart from certain phase factors) could also be significantly-well realized for {\it arbitrarily} selected LD parameters. Instead of the so-called "$\pi$-pulses" used in the previous demonstrations, the durations of the pulses applied in the present proposal are required to be accurately set within the decoherence times of the ion. % We also propose a simple approach by using only one off-resonant (e.g., blue-sideband) laser pulse to eliminate the unwanted phase factors existed in the above two-qubit operations for generating the standard CNOT gates.

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Miao Zhang, H. Y. Jia, L. F. Wei. 2008-10-13. Simplified approach to generate controlled-NOT gates with single trapped ions for arbitrary Lamb-Dicke parameters. https://doi.org/10.1016/j.optcom.2009.01.047

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