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arXiv · 1403.1524

High-fidelity preparation, gates, memory and readout of a trapped-ion quantum bit

T. P. Harty·D. T. C. Allcock·C. J. Ballance·L. Guidoni·H. A. Janacek·N. M. Linke·D. N. Stacey·D. M. Lucas
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Abstract

We implement all single-qubit operations with fidelities significantly above the minimum threshold required for fault-tolerant quantum computing, using a trapped-ion qubit stored in hyperfine "atomic clock" states of $^{43}$Ca$^+$. We measure a combined qubit state preparation and single-shot readout fidelity of 99.93%, a memory coherence time of $T^*_2=50$ seconds, and an average single-qubit gate fidelity of 99.9999%. These results are achieved in a room-temperature microfabricated surface trap, without the use of magnetic field shielding or dynamic decoupling techniques to overcome technical noise.

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T. P. Harty, D. T. C. Allcock, C. J. Ballance, L. Guidoni, H. A. Janacek, N. M. Linke, D. N. Stacey, D. M. Lucas. 2014-10-07. High-fidelity preparation, gates, memory and readout of a trapped-ion quantum bit. https://doi.org/10.1103/physrevlett.113.220501

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