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arXiv · 1001.4600

Quantum gate using qubit states separated by terahertz

K. Toyoda·S. Haze·R. Yamazaki·S. Urabe
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Abstract

A two-qubit quantum gate is realized using electronic excited states in a single ion with an energy separation on the order of a terahertz times the Planck constant as a qubit. Two phase locked lasers are used to excite a stimulated Raman transition between two metastable states $D_{3/2}$ and $D_{5/2}$ separated by 1.82 THz in a single trapped $^{40}$Ca$^+$ ion to construct a qubit, which is used as the target bit for the Cirac-Zoller two-qubit controlled NOT gate. Quantum dynamics conditioned on a motional qubit is clearly observed as a fringe reversal in Ramsey interferometry.

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K. Toyoda, S. Haze, R. Yamazaki, S. Urabe. 2010-01-26. Quantum gate using qubit states separated by terahertz. https://doi.org/10.1103/physreva.81.032322

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