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DOE OSTI · 1853028

High-Fidelity Two-Qubit Gates Using a Microelectromechanical-System-Based Beam Steering System for Individual Qubit Addressing

Wang, Ye·Crain, Stephen·Fang, Chao·Zhang, Bichen·Huang, Shilin·Liang, Qiyao·Leung, Pak Hong·Brown, Kenneth R.·Kim, Jungsang
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Abstract

In a large scale trapped atomic ion quantum computer, high-fidelity two-qubit gates need to be extended over all qubits with individual control. We realize and characterize high-fidelity two-qubit gates in a system with up to four ions using radial modes. The ions are individually addressed by two tightly focused beams steered using microelectromechanical system mirrors. We deduce a gate fidelity of 99.49(7)% in a two-ion chain and 99.30(6)% in a four-ion chain by applying a sequence of up to 21 two-qubit gates and measuring the final state fidelity. Our team characterizes the residual errors and discuss methods to further improve the gate fidelity towards values that are compatible with fault-tolerant quantum computation.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS74 ATOMIC AND MOLECULAR PHYSICSEntanglement manipulationPhysicsQuantum controlQuantum gatesQuantum information with atoms & lightQuantum information with trapped ionsTrapped ions

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Wang, Ye, Crain, Stephen, Fang, Chao, Zhang, Bichen, Huang, Shilin, Liang, Qiyao, Leung, Pak Hong, Brown, Kenneth R., Kim, Jungsang. 2020-10-06. High-Fidelity Two-Qubit Gates Using a Microelectromechanical-System-Based Beam Steering System for Individual Qubit Addressing. https://doi.org/10.1103/physrevlett.125.150505

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