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Multi-element logic gates for trapped-ion qubits



Ting Rei Tan, John P. Gaebler, Yiheng Lin, Yong Wan, Ryan S. Bowler, Dietrich G. Leibfried, David J. Wineland


Precision control over hybrid physical systems at the quantum level is of general importance in physics. For trapped-ions, a hybrid system formed of different species introduces extra degrees of freedom that can be exploited to expand and refine the control of the system. Here, we demonstrate an entangling gate between two atomic ions of different elements that can serve as an important building block of quantum information processing (QIP), quantum networking, precision spectroscopy, metrology, and quantum simulation. An entangling geometric phase gate between a 9Be+ ion and a 25Mg+ ion employing state-dependent forces is realized through a spin-spin interaction. Combined with single-qubit gates and same-species entangling gates, this mixed-element entangling gate provides a complete set of gates over such a hybrid system for universal QIP. Using a sequence of such gates, we demonstrate a Controlled-NOT (CNOT) gate and a SWAP gate in this hybrid system of dissimilar qubits. We also perform a CHSH-type Bell-inequality test on Bell states composed of different ion species.


Bell Inequality, Hybrid system, Metrology, Quantum information processing, Quantum simulation, Spectroscopy, Trapped ions


, T. , Gaebler, J. , Lin, Y. , Wan, Y. , Bowler, R. , Leibfried, D. and Wineland, D. (2015), Multi-element logic gates for trapped-ion qubits, Nature, [online], (Accessed June 22, 2024)


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Created December 17, 2015, Updated November 10, 2018